2000 S 10 Blazer 4.3 engine.
You guys were so much help to me back in 08 when the inake manifold gasket went out.
Well I am back. Same truck (my son's)
My son was loading his boat up with the engine running and it just quit.
Started it back up and it is missing bad and backfiring.
Throwing codes
PO300 Random/Multiple Cylinder Misfire Detected
PO101 Mass or Volume Air Circuit Range/Performance Problem
PO171 System too Lean (Bank 1)
PO174 System too Lean (Bank 2)
Have no clue where to start.
Suggestions Please!

 

Well I replaced the MAF today.
Engine is still backfiring bad.
The only code it is throwing now is PO300. I guess I am getting somewhere???
Really leaning towards the distributer.
Am I on the right track or would this be a waste of time and money?

 

Having the coil tested might be a good idea.

 

Will do! Thanks!

 

Got it fixed!
Replaced distributer cap, rotor, wires and plugs. Seems to have taken care of it for now.
Still showing misfire on one of the cylinders but I am pretty sure that is a injector.

 

Have you tried running some injector cleaner through it?