Is there such thing as out of balance (engine, AC fan, etc.) that cause rough idle?

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smokey_mountain

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No kidding, I will clean TB at this point by taking it off the truck. I bought new gasket for TB as well just in case. This Gen V are Throttle by Wire, so I will be the guinea pig for this forum. Maybe I should do a video to recoup some of the money I wasted trying to fix this truck while it is in full warranty ;) I am reading that varnished oil vapors is what I need to look for on the TB and butterfly to clean. I agree at 15K there should not be much to clean but... DI engine execution by GM is just low quality of design and build. Speaking from experience I cleaned MAP and MAF sensor last night using CRC MAF cleaner, noticeably better idle today. Not 100% but I think much better. I need to run it more on a hot day but from what I can tell there is improvement, so I am chasing the right problem somehow - fuel + air.
 
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smokey_mountain

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False positive on the cleaning MAF and MAP, drove quite a bit today and same old shaking flutter trembling is as bad as before. Not sure why it was better for a brief period but cleaning did not help.
 

Doubeleive

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L83 idle with the AC on, virtually no wiggle you can see the end of the dipstick wiggle a little but even holding my phone against the frame there is no video shake and the idler doesn't even wiggle
 

mikeyss

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L83 idle with the AC on, virtually no wiggle you can see the end of the dipstick wiggle a little but even holding my phone against the frame there is no video shake and the idler doesn't even wiggle

Your video reminded me of one thing I like better about the K2 vs the GMT900 engine bay.... You have PWM fans instead of just the HI/LO fans of the GMT900 . Even with your a/c on, your fans run much slower and quieter than my K5L fans. Come to think of it, I don't think I have ever heard a K2 style truck/suv run on hi.
 

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Your video reminded me of one thing I like better about the K2 vs the GMT900 engine bay.... You have PWM fans instead of just the HI/LO fans of the GMT900 . Even with your a/c on, your fans run much slower and quieter than my K5L fans. Come to think of it, I don't think I have ever heard a K2 style truck/suv run on hi.
i think these fan motors are brushless on the k2xxx that alone makes a lot of difference, there is no 500w/700w option only a option for a thicker radiator with the towing package
7/8" is regular and 1 1/8" is the enhanced cooling
 
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smokey_mountain

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There is no doubt that even Gen V DI engines can run smooth as butter, but there are also many that rough idle all the time.
 

Bob2C

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There is no doubt that even Gen V DI engines can run smooth as butter, but there are also many that rough idle all the time.
Do you by any chance have the max tow package? Duel radiator fans. I have that and wondering if there is a connection there?
 
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