Sputtering and Stuttering at Idle

Re: Sputtering and Stuttering at Idle (i.e. the stumble dance)

2012Regal GS Auto,19",Nav, CBMT, 12k miles. Has the stoplight stumble dance, but has never stalled out. Engine RPM drops to 600-700 RPM when it does the dance, normally 800-825 RPM. Doesn't matter how far I drive or what the temp is, it will dance at some lights. I use 92-93 octane. Oil has been change 2x by dealer. Everything stock except for the ScanGage II.
Pulling into the work driveway I noticed the Stability Control Light lit and the Service Trans warning on the display. Parked the GS and took the pic below. Spedo reads 37 MPH while parked. Put the trans in drive and the GS tried to lurch forward. My foot was on the brake and the Emergency brake was on so it did not move. My guess the engine speed was about 1500 RPM.
Went out about an hour later to get the codes from the ScanGageII. The GS started and looked normal. Had two codes, V0100 & P0700. Called the dealer and they gave me the option of driving it to them or getting a tow. Chose the driving option. Got about 200' away and realized it would not shift out of 1st gear. I was stuck in limp mode and did not want to drive the 20 miles in first gear. Got a 2013 Regal T3 loaner. No stumble noticed with it.
Next day picked up my GS and they said they reset the ECU (disconnected the battery?) and it's OK now. They said the problem was the ScanGage II, which I leave connected all the time since getting back from Linear Logic (Software V4.02) in early April.
Bulletin #13-08-116-001A: Aftermarket ALDL or DLC Interface Devices Causing Multiple Issues-(March22,2013) explains this issue. The dealer recommend not to leave the ScanGageII connected all the time as this
is not a warranty covered issue.
My ScanGageII has been disconnected since and will only be connected monentarily to get any codes etc. They said this was Ok.
It has been 5 days and 80 miles and no stumble dancing. I realize the ECU is still learning. Will update posts if anything changes down the road.
Drove 1500+ miles with the ScanGageII connected (still stumble dancing) with no other problems till this happened. So since the trip in the beginning of April when I first connected the ScanGageII fulltime till just last week (26 April) everything was Ok. A long post indeed, thanks for reading.
 
So has anyone had.this issue resolved?
 
Re: Sputtering and Stuttering at Idle (i.e. the stumble dance)

2012Regal GS Auto,19",Nav, CBMT, 12k miles. Has the stoplight stumble dance, but has never stalled out. Engine RPM drops to 600-700 RPM when it does the dance, normally 800-825 RPM. Doesn't matter how far I drive or what the temp is, it will dance at some lights. I use 92-93 octane. Oil has been change 2x by dealer. Everything stock except for the ScanGage II.
Pulling into the work driveway I noticed the Stability Control Light lit and the Service Trans warning on the display. Parked the GS and took the pic below. Spedo reads 37 MPH while parked. Put the trans in drive and the GS tried to lurch forward. My foot was on the brake and the Emergency brake was on so it did not move. My guess the engine speed was about 1500 RPM.
Went out about an hour later to get the codes from the ScanGageII. The GS started and looked normal. Had two codes, V0100 & P0700. Called the dealer and they gave me the option of driving it to them or getting a tow. Chose the driving option. Got about 200' away and realized it would not shift out of 1st gear. I was stuck in limp mode and did not want to drive the 20 miles in first gear. Got a 2013 Regal T3 loaner. No stumble noticed with it.
Next day picked up my GS and they said they reset the ECU (disconnected the battery?) and it's OK now. They said the problem was the ScanGage II, which I leave connected all the time since getting back from Linear Logic (Software V4.02) in early April.
Bulletin #13-08-116-001A: Aftermarket ALDL or DLC Interface Devices Causing Multiple Issues-(March22,2013) explains this issue. The dealer recommend not to leave the ScanGageII connected all the time as this
is not a warranty covered issue.
My ScanGageII has been disconnected since and will only be connected monentarily to get any codes etc. They said this was Ok.
It has been 5 days and 80 miles and no stumble dancing. I realize the ECU is still learning. Will update posts if anything changes down the road.
Drove 1500+ miles with the ScanGageII connected (still stumble dancing) with no other problems till this happened. So since the trip in the beginning of April when I first connected the ScanGageII fulltime till just last week (26 April) everything was Ok. A long post indeed, thanks for reading.

I am having/had the same issue with my car! I did not have anything plugged into the car. they have resorted to cleaning connections.... follow my post.. "I've had it (warning RANT)" good times and good luck
 
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A few thousand miles later........... Still have a slight stumble but nowhere as bad as first reported. Does not move the car like before (no dance). Have not hooked up the ScanGage since the Dealer fix. Was using a local gas station that has it's highest Octane of 92 and switched to another local station that has it's highest Octane of 93. After thousands of miles I see no different between either Octane 92 or 93. Either with the stumble, gas mileage or black carbon on the rear exhaust ports. Will not pursue the stumble problem with the dealer as it is no longer as big a problem as before. But still do not consider it fixed.
 
SO when I was running the E85 tune, I didn't get that shaky idle. It has come back since switching back to the 93 tune.
 
my rpms dance and i feel like the brakes let my car roll scared the crap out of me the first time. did it before and after tune 11 turbo😕
 
In many cases, idling problems fuel injected cars can be traced to carbon and dirt build up in the throttle body, and more specifically, in the idle air control (IAC) valve. I had a similar problem with my 1990 PA. I looked in my Haynes manual and then Googled "how to clean IAC valve GM 3800" or something similar, and came up with a host of articles and Utube videos. I found that my IAC was indeed dirty and cleaned it out with carb cleaner and a brush.

If cleaning the IAC doesn't to the trick, then the throttle body may need to be removed and cleaned out.

I hope that helps
 
In many cases, idling problems fuel injected cars can be traced to carbon and dirt build up in the throttle body, and more specifically, in the idle air control (IAC) valve. I had a similar problem with my 1990 PA. I looked in my Haynes manual and then Googled "how to clean IAC valve GM 3800" or something similar, and came up with a host of articles and Utube videos. I found that my IAC was indeed dirty and cleaned it out with carb cleaner and a brush.

If cleaning the IAC doesn't to the trick, then the throttle body may need to be removed and cleaned out.

I hope that helps


if that was the case it happen all the time not just some of the time...plus its a new car how much build up can there be?
 
Still have not talked/seen my buddy in a few weeks. The last email said he was real busy. I'll throw another reminder email at him.
 
The scary part is the technical inconsistency.

This is important. Mine did it when it was cold out, hot out, after a short drive, after a long drive, on gasoline, on E85

People who think they have figured out by length of trip or temperature are as correct as saying the problem only happens on Mondays, Tuesdays, and Fridays... This makes it harder for dealerships to diagnose when they get led to a dead end.

They replaced my engine and my high pressure fuel pump.

They replaced the whole engine?

OK, a little update on the 2.0 turbo motor. I sent a buddy of mine who works at GM an email with what my car is doing (and a link to this thread). He has forwarded my email to a few key people to find out what they know about it. Off the top of his head, he sent me this........

There is a federal mandate that the OBD2 system performs a catalytic converter efficiency test periodically. This is to be done at idle and transitioning the fuel from rich to lean. The O2 sensor output will then determine the converter efficiency. Now during this test there couldbe a perception of a near stall...but you mention there have been stalls mentioned on the forum from other customers.

He is waiting to hear back from them. I'll let you guys know when he finds something out. So here is a question for you guys........


Interesting.

Maybe it's just transitioning from open loop to closed loop and the tune is off a bit more than it should in a production car.

Maybe but probably not.

They said the problem was the ScanGage II, which I leave connected all the time since getting back from Linear Logic

That is BS.

if that was the case it happen all the time not just some of the time...plus its a new car how much build up can there be?

DI motors are terrible for carbon build up on the valves even with low miles. But I think they had nothing to do with the problems almost every Turbo is experiencing.
 
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I wanted to say that I had the same issues with my 11 Turbo and was informed by my father (former GM service manager who also had a 11 regal, but it was NA) that there was a service bulletin and solution regarding exhaust/cam solenoid (two possible issues) combined with a software upgrade, and fixing it would resolve the hesitation issue and improve my gas mileage. I did take it to the dealer and they found a code and told me it was either A) oil change sensor needed to be reset or replaced or B) exhaust solenoid. It turned out to be exhaust solenoid (I'll bring the exact part number and labor code in from the glove box and share it with you all tomorrow). They changed it a few weeks ago and INSTANTLY I felt a HUGE difference in throttle response and turbo kick from a dead stop or when accelerating at low RPMs. The car is actually fun to drive all the time, not just at higher RPMs or after it's warmed up. As for gas mileage, I haven't cycled through an entire tank of gas yet to check gas mileage (and I've been a little lead footed with the NEW engine 😉 ).


This has already been mentioned in this post, way earlier, but I think it's worth repeating. Get this checked out, it definitely made a difference for me. Insist that the dealer look into it.
 
I wanted to say that I had the same issues with my 11 Turbo and was informed by my father (former GM service manager who also had a 11 regal, but it was NA) that there was a service bulletin and solution regarding exhaust/cam solenoid (two possible issues) combined with a software upgrade, and fixing it would resolve the hesitation issue and improve my gas mileage. I did take it to the dealer and they found a code and told me it was either A) oil change sensor needed to be reset or replaced or B) exhaust solenoid. It turned out to be exhaust solenoid (I'll bring the exact part number and labor code in from the glove box and share it with you all tomorrow). They changed it a few weeks ago and INSTANTLY I felt a HUGE difference in throttle response and turbo kick from a dead stop or when accelerating at low RPMs. The car is actually fun to drive all the time, not just at higher RPMs or after it's warmed up. As for gas mileage, I haven't cycled through an entire tank of gas yet to check gas mileage (and I've been a little lead footed with the NEW engine 😉 ).


This has already been mentioned in this post, way earlier, but I think it's worth repeating. Get this checked out, it definitely made a difference for me. Insist that the dealer look into it.

No rumble while idling anymore? I'm probably going to try to get mine in next week earlier in the week. The rough idle is the most annoying thing ever. I also feel quite a jump sometime when i press gas down and i'm rolling in neutral or coming out of reverse...
 
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No rumble while idling anymore? I'm probably going to try to get mine in next week earlier in the week. The rough idle is the most annoying thing ever. I also feel quite a jump sometime when i press gas down and i'm rolling in neutral or coming out of reverse...


I never had a problem with rumble at idle. It hasn't been an issue yet
 
Hello..

New to the forum and my 2012 Buick Regal GS is experiencing the same thing, I only have 3600 miles on it.. Does anyone have an update to share on this issue.. My dealer is unable to duplicate but something is definitely wrong..

Thanks..
 
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