Problem to start

[cascades]

I am new in this forum and I have read many of the discussions amoung members. However it appears that no one as encounter my problem. I have obtained a 4 liter (line 6) fuel injected 1989 Jeep Cherokee for my son and when it begins to start it just dies instantly as if the electrical system cuts out as I release the key in the ingnition (to make sure the the starter does stay engage). I have check the following; fuel pressure and it appears to be ok at 40psi. The electrical injector connection and also ok. The ingnition coil -OK. The ignition module OK.
The things that I have not verified yet are; the CPS (crankshaft position sensor) and the regularsensorsthatarelocated on the right fender side.

Is there anyone that could help me solving this problem.

Thank you.

 

[dingus]

when my CPS went (crankshaft sensor), it wouldn't start at all, it would just crank. maybe your cat / intake is clogged... if you're chokin her down she won't stay running. best of luck and keep us posted! welcome to Jeepz.com!

 

[Bounty__Hunter]

Consider cleaning the throttle body and replacing the IAC motor (idle air contorl). It's on the front of the throttle body toward the pass. side from the throttle pos. sensor.

 

[crawlingxj]

check the injectors as well see if they are clogged

 

[Saurian]

I'm having trouble visualizing the way you are describing it... Does the starter engage and just quit WHILE you are holding the key, or does it crank over, start, and die immediately when you let off the key...

If it's the first one, I would almost think either starter, or a problem getting power to the starter, a bad ground or something of that nature...

Keep in mind, I'm not all that savvy on diagnosis, but throwing something else out there never hurts...

 

[LRwrnglr]

I had the same problem on my YJ but I have the carb. 258 so it might be a little different. We found out that the problem was the distributor. I can't remember exactly what was wrong with it but we replaced that and it started right up.

LR

 

[ebbenr]

If it dies when you let the key go, try the ballast resistor. It's the white ceramic thing on the firewall