P0300... can't figure it out

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savagebasher

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Hey all, I have a 2002 Tahoe that is throwing a P0300. 99% it only does it when towing but it's only for like 30 seconds at a time. When not towing, it has only flashed once on a road trip on the freeway.

What is odd is the truck is running perfect. I can't feel any misfire. Also, it has a fresh tune-up and the exhaust manifold gaskets have been replaced recently. Any ideas?
 

OR VietVet

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I would be worried that you have the dreaded intake leak causing the misfire. When you do it use Fel-Pro gaskets, replace the intake attaching bolts, use AC Delco knock sensors and either AC Delco wiring pigtails or Dorman. Lots of you tube info about how to do it and threads on here. Rock Auto for all parts and make sure all is very clean when reassemble.
 
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savagebasher

savagebasher

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Those were already done.. I meant to say intake gaskets not exhaust :)
 

diLucca

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I would be worried that you have the dreaded intake leak causing the misfire. When you do it use Fel-Pro gaskets, replace the intake attaching bolts, use AC Delco knock sensors and either AC Delco wiring pigtails or Dorman. Lots of you tube info about how to do it and threads on here. Rock Auto for all parts and make sure all is very clean when reassemble.

Where did you find intake bolts on rockauto? I am going to do my intake gasket and knock sensor+wiring and valley pan, BUT I cant found intake bolts anywhere. Unfortunately I am from eastearn europe, so I cant go to the dealer..
 

SLCHOE

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Power brake it and see if it misses. If you have a friend who can help, while power braking, have the friend spray the coil wires with water from a spray bottle. If the wires are arcing, you will know it.
 

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