[dan_lasater]

I have a 1995 GC. Tried to start it about 3 days ago and it will start and run for about 2 seconds then die. I checked the fuel pressure and it is at around 42 PSI. Checked the spark, got good spark. Just cant figure out if it is a vac leak or what. Any sugestions out there? It has a 4.0l with 183K miles

[Mickey_D]

Sounds like your security system is malfunctioning and thinking someone's trying to steal it. Mine does the same thing when the lights are flashing and the horn blowing. Freaked the wife out when it did it to her...

[dan_lasater]

Ya know I never thought about that. Now when yours did that did the lights and horn start blinking and honking? Because mine don't do that it just wont start and run. Please let me know.
Dan

[Mickey_D]

Yeah, mine goes all haywire if you do the following in sequence :

Lock doors with power lock switch. Close doors (SECURITY flashes on dash). Unlock doors some other way than with the key (reach in through open window or such). Open door.

At this point the lights (ALL of them) start flashing and the horn starts honking just like a real alarm system. The only way to get it to stop is to lock the doors again and open them with the key. If you try to start the engine with the security system active, it will fire then die within a second or two.

If yours isn't blowing the horn and freaking out with the lights, it might be an electrical connection from the security system to the ignition or fuel system. Either that or do we have "security" keys? You know, the ones with chips in them? If so, it might not be picking up your key...

[Mickey_D]

I just thought of something else. I seem to remember there's a signal from the ignition to the fuel pump so that if the engine isn't actually running, the fuel pump stops pumping. If that's the case, the fuel system will charge when you first turn on the key, then when you go to start it the engine will use the fuel in the pressurized system, but that fuel won't be replenished by the pump. But I don't think it would even run for a second on what little is in there. It would only catch on a cylinder or two. But I thought I'd throw the idea out there.

[turk]

Have you checked your tranny fluid? If you press on the gas and hold it will the jeep stay running? If you can give more details as to what you have experienced while trying to start the jeep it could help pinpoint the prob.

Good luck,
turk

[dan_lasater]

Havent checked the tranny fluid as of yet. If i hold the gas down it still wont run. It just dies. I havent had the chance to mess with it to much more ( gotta work lol) but I will check the fluid level and go from there. Anything else you can think of would really help. I got a little mechanical background but not to much behind a jeep. Also it doesn't matter if i put little or alot on the gas pedel it still wont run for more than a few seconds.
Dan

[turk]

For the time it runs does it idle normally or does it studder or idle high rpm?Did you check the spark plugs recently? If you hit the accelerator while its running will the engine rev? Have you kept the fuel gage on the rail from the time you start to the time the engine dies? is the pressure constant? If you hit the accelerator with the pressure guage on does the pressure drop? How much if so? Anything happen prior to this problem? Have you tried to start the jeep in neutral? Once running have you tried to put it in gear?

Turk

[sadass]

I had this problem years ago on my 93, It drove me nuts. It turned out to be the PCM (power control mod) however when I went to the dealer for the part, I was told that they do not often fail, Unless it was in a flood. I told the tech it had not been in a flood. however, I did sink it in a stream up to the middle of the front window. but there was no flood. anyway, it does seem like when the security feature is enabled, the key for me was that the horn and lights were not flashing nor beeping. good luck. let us know.

[dan_lasater]

For the time that it runs it idles normal. Checked the plugs and all are normal. The engine dosen't run long enough to do anything as I hit the accelerator. just dies right out. I kept the fuel guage on while trying to get it to run and the pressure is constant. Did not drop as I hit the accelerator. Nothing prior to this problem at all. I haven't tried to start it in neutral yet. And it wont run long enough to get it to do anything as far as try to put it into gear.

Dan

[dan_lasater]

Sadass... Funny thing , this is my wife's everyday driver. She got it stuck in a deep mud hole a few days before all this happened. if the PCM is out will it spit out a code? Also you were saying that your lights and horn did not go nuts? Anyhow tomorrow is another day and I'll keep on it till i get it figured out.

[sadass]

yep! thats correct no error codes at all and it would shut down just like when you start it with the alarm activated. but the lights were not flashing and no horn alarm. and for me it did not malfunction right after it went in the drink , it was days after as well.

[dan_lasater]

Sad,
is there any way to troubleshoot to see if that is indeed the case?

Dan

[sadass]

It has been several years, But I do remember taking some voltage readings at the relay/ fuse box under the hood. I used the Haynes and a multimeter. and I remember checking the relay for the fuel pump. and some how that led me back to the PCM. that relay ALSOhad to do with the security auto shut down. The relay coil would loose power after 2 seconds. I tryed to swap relays to no avail. I am good with schematics but I have not looked at that circuit since then. I will pull out the haynes and see if it comes back to me. I will be back on line 7pm est

[sadass]

try to swap your 30amp ASD (autoshutdown relay) with you AC relay. they are interchangable. just look under cover of box and you will see which they are. that would be my first suggestion .