Rough idle when coming to stop

2015Z71 · May 2, 2016

Are you me?

You just described exactly what I'm having AND I had to drive a loaner for the last 2 months that didn't do this at all.

Yea.. try this out though, mine will idle rough (like.. omg is this thing going to stall out?) rough in DRIVE and ONLY when warm. If its cold, no problem, if its rolling, even a little bit? no problem, reverse? no problem. ONLY drive.

Is that that what you're seeing?

You should see the water bottle I keep in my cup holder. It's a trip.

If its nothing actually WRONG.. I can put up with this, my concern is that there's some component thats gonna blow at 60,001 miles and put me like $20k in the hole for a new engine.

The only time i have noticed the rough idle so far is in drive. I have not noticed it in any other gear so far however i have not tried. I notice that that RPM gauge fluctuates between what seems to be 400 RPM and 500 RPM

darkfox1 · May 2, 2016

Yours must be worse than mine, I see no deviation in rpm.

HondaHawkGT · May 3, 2016

The only time i have noticed the rough idle so far is in drive. I have not noticed it in any other gear so far however i have not tried. I notice that that RPM gauge fluctuates between what seems to be 400 RPM and 500 RPM

http://sandyblogs.com/techlink/?p=5099

darkfox1 · May 4, 2016

Mine shakes some while at a stop but in gear. The tach is just below 500. Very annoying and I've had passengers ask me about it.

I took it into service when I had the first oil change and all the advisor told me was to get used to it as its normal.

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Not normal.. I've driven 5 K2 trucks now and 1 out of those 5 has done it. Exactly what you've described here. ~500 idle, stumbling down to 350ish and then back up to 500. At 600 (reverse or neutral it sits at 600) its smooth.

I have an appointment Thursday to hve the shop look at it.

I'm so burned out on GM's problems that if they tell me its normal I'll likely just learn to ignore my brand new $43,000 truck running like a 59 year old carb'd 283 with a poorly tuned motor.. but at this point.. I think my GM fanship will have ended.

harveyfamily · May 4, 2016

http://sandyblogs.com/techlink/?p=5099

Thank you!! I will take this back to my dealer.

2015Z71 · May 4, 2016

Has anyone had this done and seen the rough idle go away?

darkfox1 · May 4, 2016

Doesn't seem like a motor mount issue to me? I mean the RPMs hunt up and down. Maybe they always do this and I dont notice?

I dont want them pulling my motor.. I'd rather just live with this if thats what it is.I dont want them touching my powertrain again.

2015Z71 · May 4, 2016

Doesn't seem like a motor mount issue to me? I mean the RPMs hunt up and down. Maybe they always do this and I dont notice?

I dont want them pulling my motor.. I'd rather just live with this if thats what it is.I dont want them touching my powertrain again.

Agreed. I think a retune with the idle rpm at 550 or 600 would fix my issue

darkfox1 · May 4, 2016

I do too. 600 is smooth as glass. I'd just assume consume a tiny bit more gas than shim it with washers.

Shame though that I'd have to void my warranty to do that though.

2015Z71 · May 4, 2016

From my understanding if you remove the tune before it goes into service and reload the stock tune you should be ok.

thearizonacowboy · May 4, 2016

I've had a rough idle, even after tuning to idle at 600RPM. Last night I Seamfoam'd the intake and no more rough idle! Smooth as butter

2015Z71 · May 4, 2016

I've had a rough idle, even after tuning to idle at 600RPM. Last night I Seamfoam'd the intake and no more rough idle! Smooth as butter

How many miles does your truck have? Mine has 280.

thearizonacowboy · May 4, 2016

How many miles does your truck have? Mine has 280.

About 9k and I've had the rough idle for about 7k or so.

fondupot · May 4, 2016

Get some 89 octane gas in it soon, and don't use anything but 89 octane.

I am tuned to idle at 600rpm, and use only 89 octane from Top Tier stations. My truck idle's very smooth.

darkfox1 · May 4, 2016

Is there any way to have GM adjust the idle rpm like that? I mean I could talk to blackbear but considering my truck was assembled by a 2 year old on a friday at closing time.. I dont know that I want to risk my warranty.. (I hate to be so down on my truck. It's really attractive to me and when we're rolling faster than 4 and slower than 70 its wonderful. )