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theSLEEPER
Tue, October 20th, 2009, 11:10 AM
Trying to diagnose a truck. I'll look at it in an hour or so. What would cause a "miss".

These are the first things that came to mind...

CPS
Low Oil Level
Chaffed Harness
Clogged Fuel Filter

Anything else?

Power Hungry
Tue, October 20th, 2009, 10:08 PM
On a diesel? Several things...

Bad Injector Coil
Worn Injector
Bad Valve Cover Gasket
Bad UVC (Under Valve Cover) Harness
Leaking Injector O-Rings
Low Oil Pressure
Low Compression (rings, valves, etc.)
Low Fuel Pressure

I think the question is, "How bad is the miss?" Is it just a slight miss or is it a dead miss? Has anything been done to the truck recently that could be attributed to the miss? (Changed injectors, valve cover gasket, did an oil change, etc.)

On those trucks, always start with a "Buzz" test and "Cylinder Contribution" test whenever possible. They'll at least help isolate the cylinders. Since a miss can be attributed to so many things, it really comes down to vehicle inspection and process of elimination.

Good luck! :2thumbs: