remote start, 2004 grand prix

Your wiring on that external relay looks like Anti-Grind not Starter Kill. 

Being as you cut the Starter wire and inserted the relay, it now matters where you
connect the BMW 433 Violet Starter Output wire.  It should be either to Pin 87 or
on the Pin 30 side of the cut starter wire.

      Grand Prix                                                                                                        BMX 433  Thick IGN wires
12volts          red (50A)  +        back of fuse box, passenger dash
Starter           yellow  +             ignition harness                                               Purple 
Ignition          pink  +                ignition harness                                                Pink
Accessory     brown  +            ignition harness                                               Orange
 
The BMW 433 Blue/White wire should go to the 556UW Blue (-) Status Input.  If you
connect the Blue/White wire to more than one place, diode isolate the connections.

I switched the 30pin to the key side and 87a to starter side. connected the purple starter wire to the starter side 87a; 86 ign 12V, 85 GWA wire from r/s..these are all of my connections

BMW---->Car
purple wire----starter side pin 87a
orange wire----brown acc wire ign switch
red wire----WHITE/ black constant 12V ign switch
pink wire----pink ign wire ign switch
pink/white wire----pink ign wire BCM
PURPLE / white wire----tach wire at PCM, confirmed tach reading
BLACK/ white wire----park break switch wire BCM
blue/white wire----blue wire 556U

GREEN/ black wire----purple fac disarm wire
GREEN / WHITE wire----lt green fac arm wire
brown wire----white brake wire
yellow wire----(2nd)pink ign wire BCM
green wire----diode isolated door trigger wires BCM

orange wire----87a starterkill/antigrind relay
blue wire----blue pssnger unlock wire
BLACK/ white wire----tapped into green door trig wire on r/s
WHITE/ black wire----relayed to trunk release wire

brown wire---red siren wire
white wire----parking lights wire
door wires--driver door lock/unlock wires

all power wires were connected, all ground wires were properly grounded

BMW---->Car
purple wire----starter side pin 87a
orange wire----brown acc wire ign switch
red wire----WHITE/ black constant 12V ign switch
pink wire----pink ign wire ign switch
pink/white wire----pink ign wire BCM                          *******  Not Necessary
PURPLE / white wire----tach wire at PCM, confirmed tach reading
BLACK/ white wire----park break switch wire BCM
blue/white wire----blue wire 556U

GREEN/ black wire----purple fac disarm wire
GREEN / WHITE wire----lt green fac arm wire
brown wire----white brake wire
yellow wire----(2nd)pink ign wire BCM                         ******  Not Necessary
green wire----diode isolated door trigger wires BCM

orange wire----87a starterkill/antigrind relay                *****  Typo - Should be Pin 85 as noted above?
blue wire----blue pssnger unlock wire
BLACK/ white wire----tapped into green door trig wire on r/s
WHITE/ black wire----relayed to trunk release wire

brown wire---red siren wire
white wire----parking lights wire                            **** Selectable + / - output
door wires--driver door lock/unlock wires

Here is a note from DEI :
Keysense       lt. green (required)  (-)          ignition harness or BCM, conn. C1, pin 40
Bulldog, Omega and Audiovox don't say Keysense is required but if you are having issues,
try connecting it to the Blue/White GWR wire also.  Use 1N400x diodes inline to isolate the two
wires ( 556UW and Keysense ) bands toward the BMWX 433.

A diagram is worth a thousand words  :

That Green wire on the 556UW is an Input only.  It is used to sense ( watch ) for the
actual Keysense signal generated when a key is inserted into the ignition and turn off
the 556UW antenna output.  Some vehicles don't like to "see" two transponder keys at the
same time.  Unfortunately, it is not an Output that could be used to fool the vehicle into
thinking a key was inserted as DEI claims is needed. 

Here is the note from DEI :
Keysense       lt. green (required)  (-)          ignition harness or BCM, conn. C1, pin 40
 
Bulldog, Omega and Audiovox don't say Keysense is required so you might try the install without
this Keysense connection.  Watch for service or security lights during remote start or after key
takeover.

Could be a bad BMWX 433 brain.  Not sure, never used one and can't find the install manual anywhere.  Is there any sort of programming/jumper/switch for Tach Mode operation?  Any Tach Learn process prior to actual remote starter use?

What voltage reading do you get right at the battery?  Just measured two vehicles ( both less than two years old ) and got 12.15V and 12.44V at the battery.

Assuming the car works fine / normally with the key.  Also assuming the Keyless entry portion of the BMWX433 works (lock, unlock, arm, disarm, trunk release, parking lights & siren). 

Think I would try a few things. 

Verify that the Black Ground wire from the BMWX 433 is securely connected to a good chassis ground point.

Check the BMWX433 satellite relays ( ACC, IGN, Start ) for any loose / poor connections.

Connect both the Red 15 Amp and Red 30 Amp fused wires from the BMWX433 to the RED +12V constant wire at back of the fusebox under the passenger dash.

Remove the Starter Kill / Anti-Grind relay from the circuit.  Re-connect the G.P.'s cut Yellow starter wire and then connect the BMWX433's thick Purple wire to this Yellow wire.

it says to verify the tach signal, start vehicle with key. press and release valet switch 5 times within 10 sec. 6 chirps + 6 flashes indicates tach signal is picked up. Ive done this and i get the 6 flashes, i ran the tach directly off the coil by the engine. thinking about running it off the PCM, however, because the wire can be tucked away much easier. The battery gives me a read of around 11.8V, im going to let an auto shop charge it for me today. As i said before, the locks, alarm, flash lights, trunk pop all work fine. The ground wires are grounded to the same metal frame as the factory ground wires on the bolts that werent already occupied. I've tested the heavy gauge harness wires for the correct voltages with key positions, those are fine. I disconnected the starter relay and reconnected the starter wire, car starts fine with key. I need to figure out how to get to the back of the passenger fuse box. When i get my battery back, ill go about trying the remote start again. If i disconnect the bypass module completely, leave the key in the ign off position, should the remote start activate? The r/s has a loop wire dealing with auto or manual trans..i accidently cut it which is for manual, but i soldered it back together. i hope that's not causing the issue