05 chevy tahoe hesitation

[Smp13]

i have a 2005 chevy tahoe. here lately it has been missing and hesitating. no codes or check engine light. if i lay down in it , it does fine but in normal take off and driving it hesitates. could it be the plugs . i had a code a while back that showed cylinder eight misfire. and then one that said random misfire

 

[Jeff M]

I would be looking at a couple things...

The upper intake gasket is a common failure item allowing air to enter the intake by leaking past the gasket. When this happens the air is obviously not measured by the Mass Air Flow sensor and therefore not enough gasoline is injected causing a very lean mixture to be produced. This will cause the engine to stumble, idle rough and lack power. Often this condition does not produce a check engine light.

If you are getting a misfire I would be looking closely at the coil packs, it sounds as if cylinder 8 has been identified as having misfired more than once. If the intake gasket is original I would start there. Check the plastic upper intake when removed to make sure it is not warped, sometimes you need to replace it along with the gasket.

I hope this helps...

 

[Smp13]

i will replace the intake gasket and go from there.