Totally lost ---- have searched and searched and can't figure out my miss

[slippy3002]

can i get this tested with it being removed? or does it have to be on the vehicle? i have never messed with one before. and does the truck need to be warmed up when being tested since thats when its giving me issues.

Don't forget the grease on the heat sink of the module.

^ This here could be from the engine warning up.

Sent from Robl@and!

 

[IOWNJUNK]

Pull it and take it inside to be tested.

 

[Hezsus]

Rough at all RPMs? in all gears?
in my experience an ign module is all temps.
Is your air filter clean?
Fuel Filter?
Egr should have no effect on this,
If it is vaccum it will be much less noticable at higher rpms
I'd check the O2 sensor like was mentioned above to keep it in open loop.

 

[volunteerff21]

Pull it and take it inside to be tested.

What he said.

 

[withoutfear33]

Rough at all RPMs? in all gears?
in my experience an ign module is all temps.
Is your air filter clean?
Fuel Filter?
Egr should have no effect on this,
If it is vaccum it will be much less noticable at higher rpms
I'd check the O2 sensor like was mentioned above to keep it in open loop.

its only at idle no matter what gear.. you never ever feel it miss a beat when driving.. drives as smooth as can be but soon as you come to a stop it will idle okay for about 15 seconds then start to cut out and you see the rpm gauge drop a little. then idle will then strighten out for about 10 seconds then it will cut out again, just does this over and over only when its warmed up. but as soon as you take off it has tons of power and runs perfect.


i havnt had a chance to work on it yet as we just had a snow storm with a ton of ice that came last night and its about a high of 5* lol. soon as it warms up im going to start tackling it. my dogs have taken over the garage until the snow and ice stop.



also my air filter is new and my fuel filter has been changed.

 

[ernjohn]

Have you tested/adjusted your throttle position sensor (tps)?

edit: the following may or may not apply: http://www.gmtuners.com/tech/TPS_IAC.htm

 

[cviola2005]

I would definitely have the ICM checked. They can go bad in a variety of ways. They can fail for low rpm or high rpm check. Also, they can work perfect cold and mess up when hot (on either high or low rpm). When you take it in to check it, take a look at the lights on the tester. I believe there are five, but I only remember high and low rpm.

 

[Captanmactavish]

My cousins truck had similar issues. After investing 5k total into it he gave up on it and sold it for 1k to a friend. Turns out it was just the distributor.

 

[98_k1500]

Hate to put this up because it sounds stupid, that bein said i hate overlooking simple stuff. The fuel tank vent is not stopped up is it? With it warm, take the cap off the gas tank. I had a 89 that was having similar issues, but oddly enough mostly at idle. Found out the problem after leaving my fuel cap in the bed on accident after gettin gas. Truck ran great and it took me til next fill up to realize why.

 

[98_k1500]

Other than that, I would probably find a known good distributor and start there.