Engine Misfire Diagnosis on a 2005 w/4.2L I-6

[JimInRadfordVA]

Vehicle is a 2005 Trailblazer LS, 4.2, 4WD.

I've had an intermittent misfire at all RPMs with no CEL for about two weeks. CEL finally popped two days ago. Had it read and it shows a P0306 - Misfire on #6 cylinder.

Until I can dig my scan tool our of my garage (still haven't recovered from a recent move) swapping the coil pack will require going to the local O'Reilley's to have it read.

More to follow as it develops.

 

[Mooseman]

If it actually popped a code, don't wait too long so you don't kill your cat.

 

[JimInRadfordVA]

I've got three of them, and won't miss one.

Oh! You meant catalytic converter! Never mind.

 

[JimInRadfordVA]

Per Mooseman’s heads-up, https://gmtnation.com/forums/threads/another-misfire-thread.17739/ , I just ordered a set of plugs. Thanks!

 

[JimInRadfordVA]

Dodging the raindrops, I swapped the #6 coil for a used unit. Problem solved! The #6 is so far back, I had to boost up in my wheelchair and lay across the engine to reach it. I need some longer arms.

Next dry day it’ll be a set of plugs and a throttle body service.