WTF! This thing is running like crap!

Today while driving around town my truck started running rough. I glanced at my guages and noticed that my EGT's fell below 200* and I couldnt build any boost. Truck was shaking too and had a hard time maintaining speed. My injectors were also a little louder than normal. Where should I start to look? Could my injectors be on their way to the "upper room"? EBPV? Turbo took a crap? Or simply a clogged fuel filter?

Check all of the obvious stuff first. Check for a boost leak and exhaust leaks. Was it smoking when u couldnt build boost? Did it throw any codes? Do you have a fuel pressure gauge?

Sounds like you dropped a bank. The easy thing to check is the plugs on the vc harness. If all looks good there I would get it on a scanner and see which one it is. Could be any number of things.

cfdeng7 said:

Check all of the obvious stuff first. Check for a boost leak and exhaust leaks. Was it smoking when u couldnt build boost? Did it throw any codes? Do you have a fuel pressure gauge?

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Yeah it would smoke, CEL didn't light up, and no I don't have a fuel pressure guage. I checked all the boots and all are tight.

neverkickn said:

Sounds like you dropped a bank. The easy thing to check is the plugs on the vc harness. If all looks good there I would get it on a scanner and see which one it is. Could be any number of things.

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Will do this next and report back when done.

Mine did this. It was the IDM.

Just took it and ran to the store, seems to happen @50 MPH or if I hammer on it from a stop. Gotta make a trip to Baton Rouge tomorrow, when I get back in the evening I will do some more investigating.

I'm having the exact same issues and symptoms. Tomorrow ill find out what the issue is. I believe its my idm since I threw a idm failure code. And a communications error to pcm.

Sounds like the Idm if you can't find a scanner let us know also have a spare Idm you can borrow if you need it

BigStroker said:

Sounds like the Idm if you can't find a scanner let us know also have a spare Idm you can borrow if you need it

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Thanks, will probably be giving you a call this week. Y'all are in Jasper right? Been too busy this weekend to deal with it. I drove it earlier today and it seemed to run fine, but I know it did not fix itself. This crap always seems to happen when I don't have the time.

UVCH loose?

You can always unplug the VC harness and ohm the injectors and GP's before ya get ahold of a scan tool. :shrug:

Low EGT's seems weird - unless not firing injector(s) on that bank...

It seems to have fixed itself for the time being. Been running strong the past week or so, which is good. Between work and buying a house, I don't have the time to mess with it.

Dslfumes said:

It seems to have fixed itself for the time being. Been running strong the past week or so, which is good. Between work and buying a house, I don't have the time to mess with it.

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I have a feeling you aren't done with this yet. Unfortunately it will come back to you when you really don't need it to. I wouldn't be trusting the truck to any long trips till you can get it checked out.

If you've got no SES light.... then go ahead and plan on swapping out the fuel pump.


If it's running better now, then remove the fuel filter and key the truck on and note the fuel flow. Should fill the bowl completely in short order. If it's just a trickle, then you may have something clogging the line.

If it starts acting up again, key it on and lay your hand on the pump (under drivers feet on inside of framerail). The pump will cycle for 20 or so seconds each key on. If you feel/hear nothing while laying under the truck with your hand on the pump then it's done. Get another one.

If you do feel/hear it running, then pull the filter and key it on to check the fuel flow again. I expect it will be nothing, or a slight trickle.

The power required to run 50mph or so is juuuuuuuuust about as much as the injectors can syphon from the tank in many cases.


I would start by ensuring your fuel delivery system is performing as it should. Your description screams fuel starvation to me. Especially with no SES light. I'm assuming of course that there is plenty of 15w 40 in the engine.

I just changed the fuel pump a couple months ago, and the oil level is correct. I could very possibly have something clogging the line or the fuel filter needs replacing since I did fill up from the tank at work a few times. I will check this out tonight.