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2018 Yukon 5.3 4x4 "flutters" in idle in D and P, cold and warm


dvzzz

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Posted

Sorry for the double post, initially placed this in the wrong forum. My first post and my first GM truck. Came to American trucks from the world of Japanese 8-cylinders. I bought 5.3 Yukon as used with 7500 miles on it, still in warranty. While I like how this truck drives the idle seems to be unstable.

Problem:

When I stop this 2018 5.3 4x4 6-speed Yukon SLE at the traffic while transmission is in Drive (fully warmed up engine) the idle is fluttering (feels like hear misses a beat, tach needle moves a tiny bit too).

 

I am sure that dealer will not detect anything or see anything and classify all is normal, however 2019 Tahoe 5.3 that I drove in is butter smooth. I am wondering if there are ways for me to narrow down the problem with idle. I know it could be dozens of things from leaky intakes to spark plugs or injectors. I hope this community points me to the areas to check. 

 

Thank you in advance!

 
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Posted

Just had my 2018 Tahoe engine mounts replaced for same issue.. TSB 17-NA-166.. See this post as its talked about here..

 

 

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