2020 Tahoe 6.2L Misfire and Flashing engine light and Traction Control Light on

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Interlakejay

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I have a 2020 Tahoe with a 6.2L & 10 speed trans, I have a P306 misfire and engine light flashes and traction control light on. I have replaced the spark plug, and have switch the wire and coil with a different cylinder and still get a P306 misfire and traction control light. Also, when this is going on, a noise is coming from the engine/ transmission. When you clear the code, the noise goes away but will come back when lights come on. Any ideas?
 

B-train

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Are you sure it wasn't P0306? That is a number 6 misfire (maybe you already knew that and that's the one you swapped?).

Does it misfire all the time or only at certain speeds / rpm? If it's intermittent, have you tried using M9 to keep the AFM in V8 mode. If it's quiet in V8, but noisy when it goes into V4 mode, you are probably looking at lifter replacement.

How often do you change the oil? Is the sound a metallic sound - clicking / ticking noise. Should be prominent on the passenger side for #6.

The other thing I'll mention is that I had #4 bend a pushrod on my 2017 with the 6.2L. I had my friend drop a new one in, change the oil, and smack it's ass........still going strong. But, that was a slight tick at idle that got noisier with RPM - a code reader wouldn't reset it.......unfortunately. LOL
 

Miami-Dade

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@Interlakejay Moved you here from Site News.

Welcome from Queens NY&Miami Beach!
 

Joseph Garcia

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Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.
 

lt1gmc

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My #3 misfire after swapping coils, sparkplugs (that one was black on one side), wires, new injectors, checking ignition pulses, ended up being a bad lifter and cam lobe on that non-afm cylinder. had good compression and leakdown, just missing lots of lift and duration, enough to create a low speed misfire and idle roughness that went away above 2k.
 

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