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TexZ71

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TexZ71 Enthusiast

TexZ71

Posted
Posted

Issue: P0305 (cylinder 5 misfire)

 

Checked: spark plug, plug wire, & coil

 

Suggestions: please

 

Story... My 08, 5.7L, 1500, 99,583mi has been showing the above DTC. The traction control and stabilitrack turn off (fail safe to the misfire) and then turn back on under acceleration. While at idle or low speeds the fail-safe comes back.

 

Looking for suggestions, or feedback from personal experiences.

gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

5.3L maybe ,,,,

 

checked or replaced ? vaig so far Ron ,,,

 

suggest replacing the plug ,,,,ohm checking the wire ,,,scan checking the injector etc etc etc

 

intake gasket a possibility

 

 

compression of cyl ?

 

 

or take it in ,,there is lots to do ,,,,

 

stability and TCS lights are a default rather that a failsafe when the code is active ,,,you have a decent misfire and a shop will fix ya up quick ,

 

hope this helps for what its worth Ron,,,

 

if ya have the tools etc i can provide ya with the DTC chart for the code ,,,let me know

TexZ71 Enthusiast

TexZ71

Posted
  • Author
Posted

Update on the 5.3L with the defaults going off...

 

Checked the injectors by flipping around and misfire is not occurring.

 

New Issue: knocking when in drive and reverse. Knocking stops when in neutral. It's automatic... Flex plate?

TexZ71 Enthusiast

TexZ71

Posted
  • Author
Posted

Knocking/tapping occurs at operating temp maybe before too but significantly noticeable when in drive or reverse... Thinking it may be a cracked flywheel or something along those lines. Truck feels like it bounces or hops when this occurs. Seems like the throttle stutters when I try to let it coast. When I rev it it seems to drop back down to idle slowly. Not sure if this stuff helps but any feedback would be nice. I enjoy fixing my truck so please help.

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