2001 Ford F150, Hornet Remote Start

I am installing a hornet remote start/keyless entry into a 2001 Ford F150 supercrew truck. The alarm is working fine and the PATS system has been successfully bypassed with the 555F module. My problem is that the remote start will engage and the truck will run usually about 20-25 seconds and shut off.. There is a starter kill relay one of the other guys wired up for me but I don't think it is the culprit. Thje engine will also die when arming the alarm at times.. I think it only has the PATS and the factory keyless entry, I looked for the fact alarm disarm wire where tech soft said it would be and did not see it. I am stuck.. Everything seems to work except the remote start will not stay running. I am wondering if it might be a bad tach wire, this is about the best I can come up with.. I have a DEI sheet about waking up the GEM module but I didnt think that would have anything to do with engine run.. I set it with a bitwriter to 15 minutes and have tried high and low voltage threshold on tach read and still not working right.. Any help is appreciated.. Thanks

Where did you find the tach wire  for the truck ? I'm not familiar witht he DEI bypass but is it a key bypass or a keyless bypass ?

Are you using an output from the remote start system to control any external relay's? If so, they may be timed and killing a needed ignition output to the vehicle to keep it running.

Note: Your bypass shouldnt be the cause if its starting up to begin with. If it was causing some type of interference and causing it to stall,(which I have never seen) the factory theft light would be flashing.

To test for factory alarm and/or Ford Slam-Lock system, with the door open lock the door with the door switch, close the door and wait for 2min. Leave the window down and 1st. try to unlock the door from the switch. If it doesnt unlock it has the SlamLock system in it and you will have to pulse a neg. output to the door ajar wire for your remote start system to be able to unlock the door when in this mode. 2nd, open the door from the inside door latch and see if the horn pulses for factory alarm. And your right, the GEM won't cause your problem.

Hey, thanks a ton for looking at this guys.. :)

Well, I dont know what the guy did to the starter kill relay but I know that it is not hooked up correctly now.. I am going to have to peele some tape a trace a couple of wires.. He didnt install it the way I would have, though he is usually excellent with alarms. I am still not sure if it could be causing my problem..

I did check for the factory alarm by keypad locking the doors and opening doors an tapping the vehicle but there is none. It does however need the double pulse unlock I found out by testing.

I did find out yesterday when messing with the alarm that the valet switch is not working.. I tried to tach learn and tried to get into program mode without the bitwriter and neither would work. I tried 2 different switches and no luck, so I am going to doulble check all my ingnition harness connections and see whats up..

Thanks again and I'm still open to other suggestions!