Rough running at idle, after 2 hour drive...

[JOAT]

Hey Rick, good thinking on the IPR. Also it could be ran with the ICP unplugged too as a test instead of replacing it. Will set a code of course, and auto may shift in limp mode, but would be interesting to see what happens

I suppose it could be the poppet clearance too, but seems that would be more consistant injector wise.

 

[action4478]

Don ,, I thought about the the Injectors & injector O rings ,also, but , I figured the problem would be consistantly in the same hole, then you can switch the injectors around & see if the problem follows... His are also new....

 

[RoReRi]

Rick & Don,

When I unhook the ICP, just how should I go about doing it?
When the engine and key are off? I’m thinking this is the way…

Also my problem is when the engine is hot, so here is what I’m thinking.

Go ahead and drive during the day normal, come home, make sure its running rough while idling (I’m sure this will happen).
Turn ignition key off.
Unhook the ICP.
Krank her back up, and check to see if still idling rough. If its either idling rough or normal that will tell me something. Then I can go back to Rick's previous post.

If the concern is a jerky, irratic idle when hot, unplug the ICP sensor (will set a code, causes the PCM to default to a pre-selected IPR duty cycle) to see if it the idle stabilizes. If it does, check the ICP voltage with a scan tool or breakout box at pins 87 to 91 with the sensor plugged in and the key on/engine off. It should be .20-.25 volts. If the base ICP voltage is within specs, replace the IPR; If not, replace the ICP and retest.

__________________

Right?
Any other thoughts for t-shooting?


Thanks for your help!
RoReRi

 

[action4478]

Sounds like a good plan. I would do it like you said , with the key off. While you have the plug off , look at the sensor to see if there is any oil leaking out of it....

 

[Zookie400]

what type of oil are you running, and how many miles are on it? also, is the engine growing oil? we get a lot of CAT 3126 engines that have similar symptoms (hot rough, cold ok) and its something silly like beat oil, synthetic oil, or fuel in the oil.
just throwing it out there

 

[RoReRi]

what type of oil are you running, and how many miles are on it? also, is the engine growing oil? we get a lot of CAT 3126 engines that have similar symptoms (hot rough, cold ok) and its something silly like beat oil, synthetic oil, or fuel in the oil.
just throwing it out there

Shell Rotella T
maybe 2200 miles, just about time for a change, but not yet
not growing oil, loosing oil, I have a leaky valve cover and I lose about a quart in 3k miles.

Thanks!

RoReRi