help with fuel system??

[andywd]

The 87 comanche sports truck was acting like it was out of gas. I changed the fuel filter and the fuel pump. That did not fix the problem. It starts but after idling for about a minute it just sputters and dies. Then it acts like it is flooded and won't start for about another 10 minutes. I get a spark from the plugs... Anyone with any ideas?

[BLHTAZ]

Is this a 4.0L engine or a 2.5L?

 

If it's 4.0L, try bypassing the ballast resistor and see if it makes any difference.

 

It could also be a problem with the Throttle Position Sensor (TPS). You can use this to test that... http://www.comancheclub.com/forums/view ... =9&t=12260

 

Here is an electrical manual if needed... http://www.comancheclub.com/forums/view ... =9&t=12734

 

Here is the Renix FSM as well... http://www.comancheclub.com/forums/view ... =9&t=12517

[BookspanS]

Sounds like mine when I first got it....maybe bad distributor timer?

[andywd]

it is a 4.2 L engine I believe... is the distributor timer inside the cap? Because the cap was replaced not too long ago.

[BLHTAZ]

it is a 4.2 L engine I believe...

It would be a 4.0L if it is a 6 cylinder. The 4.2L, while available in some Jeeps in 1987, was never used in an MJ.

 

Do the things I recommended in my first post and see what happens :cheers:

[andywd]

I will do that thank you for the ideas.

[HOrnbrod]

Instead of throwing parts at it, invest in a cheap fuel pressure gauge and check out what the FP is doing. Sounds like your pressure regulator may be heading south.

[FxRacing282]

Instead of throwing parts at it, invest in a cheap fuel pressure gauge and check out what the FP is doing. Sounds like your pressure regulator may be heading south.

:agree: