Print Page | Close Window

1985 vw quantum, bad relay or fuel pump?

Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=128471
Printed Date: October 31, 2024 at 6:18 PM


Topic: 1985 vw quantum, bad relay or fuel pump?

Posted By: vayankee
Subject: 1985 vw quantum, bad relay or fuel pump?
Date Posted: September 08, 2011 at 2:12 PM

I have been trying to get my '85 VW Quantum running, after blowing a couple of relays that operate the fuel pump. I put a new relay in place and I now get the humming of the fuel pump for a second or two and then nothing. The car does not start. I tried using a jumper relay (87-30-86-85) and that relay lets power continue to the fuel pump, but the car still does not start.

From this description, can we conclude that the fuel pump is bad?




Replies:

Posted By: awdeclipse
Date Posted: September 08, 2011 at 3:19 PM
You get the humming for a second or two when you jump the relay or when you put the new relay in and turn on the ignition?

The fuel pump should prime when you key on, but it won't run continuously if the engine is not running.

To rule out the fuel pump you should measure the fuel pressure while jumping the fuel pump to run continuously.

I am not sure what you mean by a jumper relay? Did you short Pins 30&87 so that you bypass the relay?




Posted By: vayankee
Date Posted: September 08, 2011 at 6:48 PM

Thanks for your reply.

You asked: "You get the humming for a second or two when you jump the relay or when you put the new relay in and turn on the ignition?"  The fuel pump hums for a couple of seconds with the new relay (spades marked 87, 30, 15, 31, and 1), There is current with the key on at spades 30 and 15.

With the jumper relay, the fuel pump keeps humming. The jumper relay is one used for the x contact. It has spades 87, 30. 85. and 86.





Posted By: i am an idiot
Date Posted: September 08, 2011 at 9:40 PM
There is probably a pressure switch on the fuel line.  When the pressure is low, the pump turns on to get to the desired pressure.  The jumper relay is keeping the pump on full time. 




Posted By: oldspark
Date Posted: September 08, 2011 at 11:33 PM
From the other Quantum thread....

If the KAE relay, the pump is ONLY on when pulses are present present - was it 31b to the ignition coil -ve?
But there might be an initial turnon by the internal relay module upon power up.




Posted By: howie ll
Date Posted: September 09, 2011 at 1:43 AM
Look at another reason for it to fail. Your description of the fuel pump sounds about right. Time to borrow the VAG com.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: awdeclipse
Date Posted: September 09, 2011 at 7:43 AM
It is expected for the fuel pump to come on for a few seconds (referred to as prime) and then shut down if the engine is not running. You have confirmed this behavior.

What about when you crank the engine, does the fuel pump turn back on? If it does the the power circuit feeding your fuel pump should be fine and working as expected. You mentioned it still doesn't start with the fuel pump relay jumped so I would continue on to the next trouble shooting point. Either measure the fuel pressure or check for spark.

Is that engine PFI? TBI? I am not familiar at all with it.




Posted By: vayankee
Date Posted: September 09, 2011 at 8:51 AM

awdeclipse wrote:

It is expected for the fuel pump to come on for a few seconds (referred to as prime) and then shut down if the engine is not running. You have confirmed this behavior.

What about when you crank the engine, does the fuel pump turn back on?

>No, with the correct relay in place, it does not.

If it does the the power circuit feeding your fuel pump should be fine and working as expected.

> Since power is "interrupted" or shut off, what should I look for? Voltage regulator issues?

You mentioned it still doesn't start with the fuel pump relay jumped so I would continue on to the next trouble shooting point. Either measure the fuel pressure or check for spark.

> Yep, I tried to find spark, but could not see it. A friend is going to double check me on that tomorrow. I did find power on both sides of the coil when the key is in the on position. And there is power to the fuel pump relay slots that would be occupied by spades 30 and 15. 

Is that engine PFI? TBI? I am not familiar at all with it.


> It is called Jetronic, as used by BMW, Volvo, Audi, even Ferrari in the 80's :)

The alternator is new to me, taken from a '92 VW Golf. I did miswire it when I installed it about 3 weeks ago: I had connected the blue wire that goes to the alternator light to the body of the alternator instead of to the D+ terminal. I can't remember what symptoms told me something was wrong, but I corrected the error after talking with a Bosch rep. After that the car operated just fine. Then two weeks ago, it just quit.

Thanks for your questions!





Posted By: vayankee
Date Posted: September 09, 2011 at 9:03 AM

oldspark wrote:

From the other Quantum thread....

If the KAE relay, the pump is ONLY on when pulses are present present - was it 31b to the ignition coil -ve?
But there might be an initial turnon by the internal relay module upon power up.

Hello again! On the new KAE relay, the spade that was marked 31b on the relay that was in the car when it quit is marked 1. That corresponds to the schematic in my Bentley manual, connecting right to a #1 post on the coil. There is continuity between those points..





Posted By: howie ll
Date Posted: September 09, 2011 at 9:31 AM
Here we go with the usual catch-all answer to VAG problems...POS engine management

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: vayankee
Date Posted: September 09, 2011 at 11:46 AM

howie ll wrote:

Here we go with the usual catch-all answer to VAG problems...POS engine management

I don't understand what you mean here.





Posted By: howie ll
Date Posted: September 09, 2011 at 12:27 PM
Amongst other things the engine management units on VAG (=VW, Audi, Seat and Skoda) are a POS, they fail!

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: howie ll
Date Posted: September 09, 2011 at 12:28 PM
As do the factory immobilisers on mid-late 90s cars.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: vayankee
Date Posted: September 09, 2011 at 4:34 PM

howie ll wrote:

As do the factory immobilisers on mid-late 90s cars.

I agree that VAG stuff fails, but from my experience and that of other owners of Quantums, the ignition control moduel and the oxygen control modules on these cars are pretty good. They are not as complicated as other systems, I understand. And in this case, I suspect operator error: my miswiring or misconnecting or missing something wrong out of ignorance. That's why I wrote to this forum. 





Posted By: oldspark
Date Posted: September 13, 2011 at 3:57 AM
Hall/vane ign sensors "not as complex"... Oh I'm so glad I have a Jap reluctor system (and the Lucas Rita).

And spark sensing for fuel pump? By definition, that is complex. (As I wrote recently, it should be done by the ECU/EMS, not the relay.)
They should have used the carby system - eg: an alternator-(charge-light-)controlled SPDT relay with STARTER priming (via 87a) else charge-lamp via diode - and starter via diode - to energise a SPST relay. 2 diodes else extra mechanical contacts/switching instead of a spike-suppressed pulse sensor (ie, at least a capacitor else heating vane etc...).
Plus the power-on primer if required...





Posted By: oldspark
Date Posted: September 13, 2011 at 4:11 AM
PS:

vayankee wrote:

awdeclipse wrote:

What about when you crank the engine, does the fuel pump turn back on?

>No, with the correct relay in place, it does not.


IMO the correct relay should pump when cranking - that is an essential part of fuel pump control - ie, it pumps when cranking and when the engine is running.


EFI systems (and some carby systems) also add the "pre-start" priming - ie, when the IGN is first turned on (pumps for up to a few seconds)


If your pump is NOT pumping with the CORRECT relay fitted, then the signal from the coil- is faulty, else that module in the relay is faulty.

If I misunderstand the operation of that relay, then fine. But in that case, what turns the pump on whilst cranking? For EFI, it MUST be pumping when cranking. (Carby systems may start without it.)




Posted By: vayankee
Date Posted: September 13, 2011 at 7:52 AM

oldspark wrote:

Hall/vane ign sensors "not as complex"... Oh I'm so glad I have a Jap reluctor system (and the Lucas Rita).

> Fortunately, I wrote "not as"; unfortunately, I did not write "compared to later VW engine management, namely, Motronic."

And spark sensing for fuel pump? By definition, that is complex. (As I wrote recently, it should be done by the ECU/EMS, not the relay.)

> I could but will not debate complexity theory with you, but I believe that you are right about the ECU's role. Actually, I suspect that the relay and the ECU are interconnected so both "control" (that culturally-loaded word) the spark sensing that takes place at the fuel pump.

>Since we last commented here, three experienced VW guys have pointed to the ECU as a source of the non-starting in my case. This is not to condemn the ECU as poorly designed, but I suspect as the result of my mistesting the fuel pump wiring, thereby blowing two good fuel pump relays and possibly my ECU, and maybe more stuff. Again fortunately, yesterday my VW mechanic loaned me 4 ecus off his shelf to try out. trying them out is my project for this morning.

They should have used the carby system - eg: an alternator-(charge-light-)controlled SPDT relay with STARTER priming (via 87a) else charge-lamp via diode - and starter via diode - to energise a SPST relay. 2 diodes else extra mechanical contacts/switching instead of a spike-suppressed pulse sensor (ie, at least a capacitor else heating vane etc...).
Plus the power-on primer if required...

>I can't comment here, except to say that I hear NASCAR is going to move away from carburetors. As I said earlier, I am not a engineer, but I do value our environment, and if FI and ECU's are better at controlling pollution, I have to favor that solution. And speaking of carburetors, the last car I had with a carb was a 1980 FWD Subaru. That car did not want to do much in terms of high speed, so driving coast to coast back in 1988 was not exactly fun. I didn't expect anything from it after learning that the nothing could be done to to carb to enhance its capabilities. Again, from a non-engineer.






Posted By: vayankee
Date Posted: September 13, 2011 at 7:57 AM

oldspark wrote:

PS:

vayankee wrote:

awdeclipse wrote:

What about when you crank the engine, does the fuel pump turn back on?

>No, with the correct relay in place, it does not.


IMO the correct relay should pump when cranking - that is an essential part of fuel pump control - ie, it pumps when cranking and when the engine is running.


EFI systems (and some carby systems) also add the "pre-start" priming - ie, when the IGN is first turned on (pumps for up to a few seconds)


If your pump is NOT pumping with the CORRECT relay fitted, then the signal from the coil- is faulty, else that module in the relay is faulty.

If I misunderstand the operation of that relay, then fine. But in that case, what turns the pump on whilst cranking? For EFI, it MUST be pumping when cranking. (Carby systems may start without it.)

Yes, it would seem that the pump should operate when the engine is cranking. But maybe there is a signal telling the pump not to work if the engine does not have spark. I'll check and let you know on this.





Posted By: oldspark
Date Posted: September 14, 2011 at 3:26 AM
That relay only senses spark - not cranking.
So if no spark, you'll only get the initial power-up pumping for a few seconds.



PS - I missed the previous reply...

The complexity is simply the circuitry. Ignoring Power-On priming, the alternator & cranking version is merely 2 diodes plus the relay. Spark sensing requires more components and the same relay, hence more likely to fail. (Diodes are the most reliable solid-state device. Spark sensing involves capacitors which are more prone to failure, plus transistors which are diodes with a bit extra.)

Spark-sensing is used for total loss systems (battery only - no alternator) else as a redundancy for alternator or air-flap sensing.



The ECU isn't a bad design per se, I see it more of an oversight (though nothing beats Delco).
Other K-Jetronic vehicles use a spark-sensing relay so I suspect fuel-pump control is not included in the ECU (IMO that's strange since priming is essential to prevent injector damage etc).

But either the ECU controls the pump, else it doesn't. If there is ECU control, there should be no reason to use anything but an ordinary SPST relay.


And again, as I understand that KAE 3.300.210 relay (as per your other thread), it has internal circuitry for spark control (and presumably the power-on priming - ie, a power-on high for a few seconds). That is used INSTEAD of ECU control. It does not make sense that the 3.300.210 would be used if there was ECU control - ie, IMO it is intended for carby systems without an ECU (or early aftermarket ECU/EFI systems - ie, those with analog ECUs & pot adjustments etc).


If it were my car, I'd junk that relay and use an ordinary SPST relay with diodes from the alternator (regulator's charge light circuit) and cranking signal (ignoring its connections to the "voltage" relay). The power-on prime could be as simple as a capacitor, else an R + C delay with transistor or FET switching.




Posted By: vayankee
Date Posted: September 15, 2011 at 5:56 PM

oldspark wrote:

That relay only senses spark - not cranking.
So if no spark, you'll only get the initial power-up pumping for a few seconds.



PS - I missed the previous reply...

The complexity is simply the circuitry. Ignoring Power-On priming, the alternator & cranking version is merely 2 diodes plus the relay. Spark sensing requires more components and the same relay, hence more likely to fail. (Diodes are the most reliable solid-state device. Spark sensing involves capacitors which are more prone to failure, plus transistors which are diodes with a bit extra.)

> I think I see your argument-keep it simple so less chance of failure. And that is what happened, though I was the cause of the failure. But on the other hand, I don't hear of a lot of failures. By that I mean, my mechanic and my Quantum owners' group would be quick to yell about something like this that gave out a great deal. Yes, the fuel pump relay of mine and others have quit, and it is inconvenient, but we are talking about cars that are about 20 years old with lots of miles, and usually are driven in tough conditions-daily drivers in northern climes.

Spark-sensing is used for total loss systems (battery only - no alternator) else as a redundancy for alternator or air-flap sensing.



The ECU isn't a bad design per se, I see it more of an oversight (though nothing beats Delco).
Other K-Jetronic vehicles use a spark-sensing relay so I suspect fuel-pump control is not included in the ECU (IMO that's strange since priming is essential to prevent injector damage etc).

> I don't understand why you and the other fellow use such strong language here. The ignition control unit in this system lasts a long time, gives great economy, has been very reliable. I again am not an engineer to criticize or praise how something is designed, but when results are favorable, how bad can it be?

But either the ECU controls the pump, else it doesn't. If there is ECU control, there should be no reason to use anything but an ordinary SPST relay.

>Again here, I can not comment, and I am sorry to say I will not be able to understand any technical insights on this point.


And again, as I understand that KAE 3.300.210 relay (as per your other thread), it has internal circuitry for spark control (and presumably the power-on priming - ie, a power-on high for a few seconds). That is used INSTEAD of ECU control. It does not make sense that the 3.300.210 would be used if there was ECU control - ie, IMO it is intended for carby systems without an ECU (or early aftermarket ECU/EFI systems - ie, those with analog ECUs & pot adjustments etc).

> You have made your point. but I think if you want to argue a point like this you should engage someone who is able to respond.


If it were my car, I'd junk that relay and use an ordinary SPST relay with diodes from the alternator (regulator's charge light circuit) and cranking signal (ignoring its connections to the "voltage" relay). The power-on prime could be as simple as a capacitor, else an R + C delay with transistor or FET switching.


> I know you say "if it were my car," but that does not make your argument any stronger. In fact, it is a bit of an insult, when I don't have thetechnical wherewithal to argue with you.

I am sorry if I offend you, but this discussion seems to be to be getting out of hand. i did appreciate hearing from you on the basics of relays, but going beyond that into design changes that you feel so strongly about is worrisome to me.





Posted By: oldspark
Date Posted: September 15, 2011 at 8:42 PM
No offense taken, and no IMO strong language.

As I understand it, your system is simple.
There is no interaction between the Jetronic and the fuel pump.   
The fuel pump is solely controlled by the relay which merely senses spark, and has an initial power-on priming "pulse".
Hence you fuel pump only operates when IGN is first turned on (for a few seconds) and then when spark is present - hence meeting both safety and engine requirements.   

If so, the discussions with ECU interaction were irrelevant (maybe out of hand so to speak).


These days ECUs control the fuel pump, and usually ignition (advance & retard). IMO these were always possible and simple to implement (except ignition for analog ECUs) and fuel pump control should always have been a part of EFI design - it simple ECU logic programming or circuitry with a single output to the fuel pump relay. But I am and was often well in advance of auto manufacturers in such matters.   
[ And I compare to other systems which at the time were fully electronic - ignition and injection were totally ECU controlled, the distributor had no vacuum or speed advance mechanisms. ]


Bottom line is that if that relay is reliable, then stick with it. And though easy to bypass (just a wire link), its cheap enough to carry a spare.

The system I described is for the DIYers - those that want a simple and cheap system that uses common parts (an SPST or SPDT relay etc) and can be extended (eg, a manual switch to pump with the engine off). And it can be used by those with difficulties sourcing or affording the original relay.
It is also easy to test. Yours isn't - you must provide ignition pulses to check the relay's operation. For DIYers, that means ensuring the vehicle is sparking, and the connection to the relay is sound.


PS - I also missed your 2nd last para. Sorry - I meant no offense. You did not design your car nor the Bosch system. I did not mean that statement as a design criticism, but simply as my preferred solution. (I like readily available components and redundancy.)

[ The design IMO is as stated above. Why did they NOT implement what others had, and what they now implement, and why did they change from that old implementation? It is an argument of simple logic (pun unintended) rather than technical. If the ECU provides "engine running pulses" (ignition or injectors), then why duplicate that elsewhere? It's not redundancy because if there are no ECU pulses, then the pump is not required (and for safety reasons, must be off). I'd like to know if they had technical reasons... ]




Posted By: vayankee
Date Posted: September 16, 2011 at 8:26 AM

Very good overview, thanks.

As one limited in electronics, a pull and replace strategy probably should be adequate. But inability to test any one component is frustrating. But that is a much larger issue.

After my mistesting of the system, leading to blowing at least two fuel pump relays, I probably should be furious. But thanks to people like you, I have learned from the experience.

Hang in there!





Posted By: oldspark
Date Posted: September 17, 2011 at 12:32 AM
I have just reread the entire thread. (With thanks to my master for that inspiration!)


Your problem is simple - the relay is not getting its spark signal.
That is quite clear from the early posts. The pump pumps with a normal relay (with IGN on - as it should).
Good proper relays are not pumping when the engine turns. That means it is not seeing the spark signal - it merely does its initial-power on thing.

What awdeclipse and then howie ll wrote were spot on, and i am not an idiot added a reason for the initial turn-on that you were hearing (since found to be a power-on timer function in the relay).

I or we then got into semantics. I certainly lost track that the relay was NOT the problem.


So...
Does the car start with the jumper relay? (...whether a standard SPST relay else a jumper between 30 & 87 in which case the pump should be running when the IGN is on.)
If yes, your relay is not seeing spark.

If no, you are probably not sparking. Hence check spark with a splug HT lead connected to an external splug whose body is shorted to the engine or GND.
No spark? Check with the IgCoil HT direct to the grounded spark.
Yes spark? Bad dizzy cap and rotor or leads.
No spark? Normally check the coil's HT lead (swap with dizzy-cap to splug lead), but since the relay isn't seeing spark, it's almost certain the IgCoil- is not being pulsed.   
So then diagnose that. "How to" later if required - I suggest a new "spark" thread.

If sparking and pump running, then check fuel flow, but more on that later if needed.


But it seems your problem is no spark - specifically no pulses to the IgCoil.




Posted By: vayankee
Date Posted: September 17, 2011 at 8:03 AM

After further review at my end, and input from others, the problem was complicated by no spark, as you wrote, and bad relays, as self-inflicted wounds (I apparently fried the two backup fuel pump relays by crossing my voltmeter's wires on the connection at the fuel pump-the connector's wires were actually crossed in the connector boot). The car now starts but stalls after 3-4 seconds.

I am not sure how to continue with this story. But I believe that I should start a new thread. I will title it "Engine starts and stalls."

Thanks for your input and patience with me!

 





Posted By: vayankee
Date Posted: September 17, 2011 at 8:43 AM

I have a 1985 VW Quantum, 4 cylinder, 1.8L engine that starts and stalls within 3-4 seconds.

I can hear the fuel pump operating with the key in the on position, and then, after the engine stalls, I can hear the fuel pump still running. There is voltage on either side of the coil. The engine seems to be running pretty smoothly after starting. I tried pedal to the floor but it made no difference.

The FI system is Jetronic CIS-E. There is some background that I believe is pertinent. A couple of weeks ago, while out driving, the car was running very well when it stalled. I was able to restart it by engaging second gear, so I turned around and headed home. On the way home it stalled again and I could not start it. For a couple of days I tried checking wires, since I had earlier found several sections of wiring/connections that were bad or suspect. But as I said the car was running very well when it stalled.

Then I realized that the fuel pump was not running when I tried to start it-you can normally hear the pump priming/pressurizing with the key in the on position. I tried checking the voltage to the fuel pump rather than just inserting a new fuel pump relay. Unfortunately I misconnected the voltmeter's wires at the fuel pump connector-under the connector's boot, the wires had been crossed, so in fact I put the meter's common to the hot wire and the hot meter lead to ground. I believe that I fried two back up fuel pump relays that way. A friend confirmed that the three relays (the original and the two back ups were bad).

The friend also confirmed that the engine had no spark. Several others suggested at that point that the ignition control module was bad. They were right. My VW mechanic had some used ones for me to try. Two of them worked-the engine started, and then stalled after 3-4 seconds. I kept one of the good modules and returned the others.

The mechanic could not suggest anything else to try. But we agreed that my error with the fuel pump relays could have damaged something else, and the most likely culprit is the idle stabilization control unit. It looks like a relay,  and it is located in the relay panel. The part number, now memorized, is 811905343. It is connected to the negative side of the coil, post one, just as the ignition module is. Inside it are resistors and an IC-no mechanical coil/relay.

The mechanic said he did not know how to test it. I wrote to Telefunken asking for help testing it, but I got no answer. The only method I can think of is to switch it with a known good one in a car that runs. I am hesitant to buy a new one (cheapest -116.00) until I am sure that mine is bad. This part was also used on US spec base-model Golfs and Jettas from 1985 to 1987, but local junk yards have none of these cars anymore. Interestingly, I found the same part was used on Euro-spec Audi 80s from 1985 to 1991, and the used parts themselves are for sale on the internet through Swedish car dismantlers. I wrote to one in English but I have not heard back from them

Anyone's thoughts on this diagnosis, etc?





Posted By: oldspark
Date Posted: September 18, 2011 at 7:24 AM
So it stalls with the bypass relay (standard SPST relay)?

I'm just confirming since it is obvious the pump would not continue pumping after a stall if using the correct (original type) relay.




Posted By: vayankee
Date Posted: September 18, 2011 at 9:26 AM

oldspark wrote:

So it stalls with the bypass relay (standard SPST relay)?

I'm just confirming since it is obvious the pump would not continue pumping after a stall if using the correct (original type) relay.

Good question. I am not using a "jumper" relay. I should have mentioned that the "new" relay is not exactly the same as the relay that was in place when the engine originally stalled. That one and the two back ups that I tried had the following spades: 15, 30, 87, 31 and 31b. The new one has 15, 30 31, 87 and 1 spades. The no.1 spade or rather slot in the panel is connected directly to the no 1 post on the coil and to the idle stabilization control unit, if I am reading the diagram correctly.

So when the engine stalls and the key is still in the run/start position, wouldn't the fuel pump still be "on" or presurizing, so that the operator can just turn the key to the "start" position?





Posted By: vayankee
Date Posted: September 18, 2011 at 9:58 AM
Now that I think about it, the fuel pump still running after the engine stalls does not sound like a good idea. But why is it running? Could the ignition switch be fouled up, again because of the mistesting I did? I have read that the "electrical" section of the ignition switch can be shorted out through crossing wires.




Posted By: howie ll
Date Posted: September 18, 2011 at 10:42 AM
There's NO electrical parts in an ignition switch. 2 switch contacts, ACC and ignition 1 and 2 and a sprung contact for the starter.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: oldspark
Date Posted: September 18, 2011 at 12:19 PM
No, the pump should not run with the engine stalled with the proper relay - it is only closed when THE SPARK IS PRESENT (and during power up).

Bypass the relay with a wire link.




Posted By: howie ll
Date Posted: September 18, 2011 at 5:38 PM
Duff coil?
Duff HT leads?
Duff EManagement?
Dirt or gunge in fuel lines, any thing but the bloody fuel pump?

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: howie ll
Date Posted: September 18, 2011 at 5:39 PM
In fact on a vehicle of that age my first guess would be coil breaking down.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: vayankee
Date Posted: September 18, 2011 at 5:42 PM

oldspark wrote:

No, the pump should not run with the engine stalled with the proper relay - it is only closed when THE SPARK IS PRESENT (and during power up).

Bypass the relay with a wire link.

OK. I just checked again on the fuel pump. When the engine stalls, the pump runs for just 2-3 seconds at most and then stops.

Then I decided to try all the fuel pump relays that I have, including the old "bad" ones and the new ones, They all "worked" just the same, regardless of whether the fifth spade is maked 31b or 1. But the engine stalls after 3-4 seconds. This is all with the replacement ignition module in place.





Posted By: vayankee
Date Posted: September 18, 2011 at 5:56 PM

howie ll wrote:

Duff coil?
Duff HT leads?
Duff EManagement?
Dirt or gunge in fuel lines, any thing but the bloody fuel pump?

Thanks for your suggestions. On the coil, I tested it per the service manual for resistance within spec. The HT (line to distributor) to the no 1 post, (negative side) was within spec. However, the resistance between positive and negative sides was .93 ohms, .17 ohms higher than called for. .52-.76. However that is the resistance I have been reading there from several checks in the past, and it is the same resistance as on two back-up (tho used) coils that I have.

I don't have a test for the HT lead itself. It is about 3 years old, or only 5k miles.

The Engine management apparently was at fault, but . . . I replaced the ignition module and it now starts but dies. I also switched out the oxygen sensor control unit but that did not make a difference.

On gunk in the fuel line, I have not checked on that yet, as I was waiting for my neighbor to have some time to help.

I still wonder about, and am looking for a replacement, idle stabilization control unit which is tied into the oxygen control unit.





Posted By: vayankee
Date Posted: September 18, 2011 at 6:00 PM

howie ll wrote:

There's NO electrical parts in an ignition switch. 2 switch contacts, ACC and ignition 1 and 2 and a sprung contact for the starter.

Yeah, but VW has an intermediate part that the current goes through right before the switch. They call it the electrical part of the switch. I have not had it out to check it, but they are widely available for replacement, which suggests some sort of wear or failure could/does occur there.





Posted By: howie ll
Date Posted: September 18, 2011 at 6:12 PM
Never seen anything like that on a VW, was the Quantum what we called the Passat by the way? The only thing electrical is the wiring connector and yes they often burned out on VWs of that age.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: vayankee
Date Posted: September 18, 2011 at 7:01 PM

howie ll wrote:

Never seen anything like that on a VW, was the Quantum what we called the Passat by the way? The only thing electrical is the wiring connector and yes they often burned out on VWs of that age.

Yes, the Passat was the original name, I believe.

The wiring connector is probably what we are telking about. The wires themselves come in to a curved black connector, which attaches to a white capsule connected to the switch. That capsule is what they/we call the electrical part of the switch.

As I say I did not pull that apart yet. I was warned to watch out for the plastic ring/collar that sits on top of the metal switch assembly when I try to pull it off the steering column. So I hesitated, thinking that the whole switch was ok since the engine started. Is it possible that that fail-prone part could cause the engine to cut off after 3-4 seconds? I don't know what symptoms of failure of that piece are.





Posted By: oldspark
Date Posted: September 18, 2011 at 8:09 PM
vayankee wrote:

I don't have a test for the HT lead itself. It is about 3 years old, or only 5k miles.
That is SO WRONG! Please correct your ignorance. (Not meant as an insult, but merely a lack of knowledge and reality. But also 3 years & 5k is not new - it can break on installation if not before.)
PS (orig post time + 10 hours) - I can accept "I shouldn't have to test...", but the applicable statement is "You shall test..."

vayankee wrote:

That capsule is what they/we call the electrical part of the switch.
Ah - so the switch is merely a mechanical device without any electrical connectors.

REPLACE THE RELAY WITH A JUMPER. Else a standard relay. I want to ensure the pump is running all the time when IGN is on.
There is no point continuing until that is established.




Posted By: vayankee
Date Posted: September 19, 2011 at 1:52 PM

oldspark wrote:

vayankee wrote:

I don't have a test for the HT lead itself. It is about 3 years old, or only 5k miles.
That is SO WRONG! Please correct your ignorance. (Not meant as an insult, but merely a lack of knowledge and reality. But also 3 years & 5k is not new - it can break on installation if not before.)
PS (orig post time + 10 hours) - I can accept "I shouldn't have to test...", but the applicable statement is "You shall test..."

> While sticks and stones can break my bones, etc. I would appreciate your leaving out personal attacks. I know I am ignorant about this stuff-otherwise I would not have written in! Please!  And yes, I realize that ignition wires fail, but I have enough experience to know when they are failing. I simply pointed out that my wires are performing fine. And all I really wanted was to find out out to test them. You didn't answer that question. So I double-checked the service manual, ran the resistance test, and they are fine.

vayankee wrote:

That capsule is what they/we call the electrical part of the switch.
Ah - so the switch is merely a mechanical device without any electrical connectors.

>I don't know what your point is here. Are you being sarcastic? Of course it has electrical connectors.-that's what I wrote above.

REPLACE THE RELAY WITH A JUMPER. Else a standard relay. I want to ensure the pump is running all the time when IGN is on. There is no point continuing until that is established.


Yes, the fuel pump runs full time, with the key in the on position, and after the engine stalls, when there is a non-fuel pump relay (87,86, 85,30) in the fuel pump relay position. And the fuel pump does not stop until I turn off the key.





Posted By: oldspark
Date Posted: September 19, 2011 at 7:57 PM
Again it is NOT a personal attack. I thought that was quite clear from my follow up. I didn't know what other term to use other than ignorance without verbiage that meant the same thing. (Remember, I write technical, not social trend english).

But if you do not NOW understand or see that, please let me know so I have drop this thread before I insult any further. Sticks & stones - how insulting!

A resistance test in inadequate for HT lead testing. It is to be tested in situ with HT coil and a splug.

AFAIAConcerned, HT lead and spark reliability was not established.

No sarcasm on the switch. In my parlance, the switch is electrical. Anything else is the actuator. I was reflecting that your "switch" is my "actuator". Now I know how to reinterpret your writing, and define my "switch".

So yes, you have a "jumper" relay and the engine still stalls.
Cool, now we can move on. Ignition testing after the coil is now irrelevant. Next stage IMO is sensors.    

But, are you able to take my technical language without posting offense?




Posted By: howie ll
Date Posted: September 20, 2011 at 3:18 AM
This whole thread is getting rather silly and I'm surprised the moderators haven't pulled it.
The poster has now started two threads with incorrect assumptions, i.e. fuel pump and relays, has questioned ALL our comments, based in my case on 40 years of auto-electrical and diagnostic experience, in Oldspark's case 25 + as an electronics engineer.
You've burnt out at least one relay from bad testing.
Coil and HT leads are running into reactive loads, a continuity test at rest will tell you nothing! Think of a speaker with a nominal 4 ohms (IMPEDANCE not RESISTANCE). That will change as different frequencies are fed to it.
Again look at engine management or test the voltage from the BLACK lead at the ignition switch when you start and try to run the car.
Please change your attitude or any future posts are going to get no replies.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.




Posted By: vayankee
Date Posted: September 20, 2011 at 7:56 AM

howie ll wrote:

This whole thread is getting rather silly and I'm surprised the moderators haven't pulled it.
The poster has now started two threads with incorrect assumptions, i.e. fuel pump and relays, has questioned ALL our comments, based in my case on 40 years of auto-electrical and diagnostic experience, in Oldspark's case 25 + as an electronics engineer.
You've burnt out at least one relay from bad testing.
Coil and HT leads are running into reactive loads, a continuity test at rest will tell you nothing! Think of a speaker with a nominal 4 ohms (IMPEDANCE not RESISTANCE). That will change as different frequencies are fed to it.
Again look at engine management or test the voltage from the BLACK lead at the ignition switch when you start and try to run the car.
Please change your attitude or any future posts are going to get no replies.

Thanks for the help you have given me here. However we are definitely on different wavelenghs here in terms of how we discuss these issues. So I withdraw my questions.. 





Posted By: vayankee
Date Posted: September 20, 2011 at 7:58 AM

oldspark wrote:

Again it is NOT a personal attack. I thought that was quite clear from my follow up. I didn't know what other term to use other than ignorance without verbiage that meant the same thing. (Remember, I write technical, not social trend english).

But if you do not NOW understand or see that, please let me know so I have drop this thread before I insult any further. Sticks & stones - how insulting!

A resistance test in inadequate for HT lead testing. It is to be tested in situ with HT coil and a splug.

AFAIAConcerned, HT lead and spark reliability was not established.


No sarcasm on the switch. In my parlance, the switch is electrical. Anything else is the actuator. I was reflecting that your "switch" is my "actuator". Now I know how to reinterpret your writing, and define my "switch".


So yes, you have a "jumper" relay and the engine still stalls.
Cool, now we can move on. Ignition testing after the coil is now irrelevant. Next stage IMO is sensors.    


But, are you able to take my technical language without posting offense?


Thanks for the help you have given me here. However we are definitely on different wavelenghs here in terms of how we discuss these issues. So I withdraw my questions.. 





Posted By: the12volt
Date Posted: September 20, 2011 at 8:33 AM
Duplicate topics merged and closed.

-------------
posted_image the12volt • Support the12volt.com





Print Page | Close Window