Grounding issues?

[xulferdica]

I have a 2000 GMC Yukon XL that has misfires and has crazy gauge fluctuations when first started but when I run it through a car wash or it rains for several days the check engine light goes off and it runs great until it dries off. I’ve checked almost everything and replaced the ECU. Is this a grounding issue?

Thanks for any thoughts!

 

[drakon543]

sounds feasible its about the only thing that would work better if it was wet

 

[Big Mama]

The battery ground on these is suspect they get corroded at the chassis

 

[NardDog]

I would guess water in the knock sensors

But the ground is easy to check its on the bottom drivers side of the engine toward the front. Below the pS pump. Just remove clean and reinstall.

 

[NardDog]

I would guess water in the knock sensors

But the ground is easy to check its on the bottom drivers side of the engine toward the front. Below the pS pump. Just remove clean and reinstall.

 

[NardDog]

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[NardDog]

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[NardDog]

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