Hi All,

Just a quick update on the issue that a few people seem to be experiencing with hesitation, engine flare, transmission slip, etc. I got the following TSB from my dealer the other day. I have had this procedure performed twice (which appears to be the maximum allowable before they start looking at other problems) without any resolution. I recently had a data recorder placed in my vehicle and was able to recording the engine flare which the tech noticed. The RPM's flare to about 2000 without any throttle position and the vehicle not moving and unable to accelerate. I also recorded it with my video camera to show the tech at the dealer. They are waiting for GM's response as they sent all the data along for review.

It looks as though they know this is a problem, but don't have a solid resolution. This TSB is the third revision. The previous one was titled something like Hybrid Driveability concerns. Anyway, I'm just trying to keep the lines of communication open. If anyone has had these problems, please report so we can find a fix. Thanks.

 

This friday 9/24/10 I am going back to the dealer (Castrucci Chevrolet Milford Ohio) as the TSB that kecusc attached lists 75% of the issues that we have experienced. Hopefully this will help our issue out? My only concern is that if this doesn't fix the issue and other parts in the transmission need replaced is this considered, my warranty runs out in a year or 12000 miles on bumper to bumper. If this is considered a Hybrid part of the 8 yr warranty then we are fine, if it isn't then I may have issues. Will have to discuss with the dealer. Will keep you posted.

 

Hi there, I was just curious if your running problems are still acting up or did it seems to fix itself after time like mine did?

Mine started to run like yours for a couple of days right after I had put in $30.00 worth of 87 octane fuel at a circle k store that i have used many time before in the past, it is a very busy store that sales union 76 gas without any issues from the past in either one of my vehicles, Until that one time about a month ago, But it seemed to start to run a little better as time went on, And as soon as I went back to using 89 octane chevron it cleared right up and haven't noticed the running issues at all anymore.

The vehicle now has 22000 miles and I have noticed that over all, it seems to runs much better using any grade of octane at chevron fuel stations versus using all the other fuel brands and octanes out on the market here in So-Cal.

Curious to know if anyone else has noticed anything like that between the fuel brands, ect?

Thanks.

 

Fun Time, The issues that are being discussed in this thread in my mind deal strictly with the hybrid system, not the ICE. The reason I state this is because the engine isn't running when these issue's are occuring in my vehicle, I can't speak for everyone though.

 

Hi wsumsd98, Sorry about that, I was not trying to change the subject of how the vehicles where running.

I reread the hole thread again, And everyone's description of how the vehicle was running at the time was pretty much how mine was running for the almost two days in a row, But as time went on I could tell/feel the vehicle was getting better, Not running so rough at idle, Hesitant on acceleration whether it was in auto stop or engine running. The hesitant was so bad at times that on acceleration the front of the vehicle would dip down a few inches almost throwing your upper body forward, then it would throw you back hard up against the seat once you got going.

Also at times if I let off the brake pedal and a gave a quick tap on the accessorator pedal and I believe I reapplied the brake pedal (Sometimes), The engine would rev up to 2000 RPM's on it's own and stay there, Then as i let off the brake pedal slowly the vehicle would slowly start to take off, But not at a fast speed like if I was trying to take off fast at 2000 RPM's or more, It would just ease up slowly in speed.

Also in that time frame the engine stalled one time as soon as I put it into forward gear. I had just shut the engine down in a parking lot and realized I had better pull the vehicle up a few more inches, Because I thought I was sticking out to far into the parking lot, So I quickly restarted the engine and quickly put it into forward gear and it stalled as I was lightly touching the accessorator pedal, And the vehicle was rolling backwards with no engine power at all, I had to stop the vehicle, Put it in neutral to restart the engine, And that required turning the key about four times before the engine would start just so I could repark the vehicle.

Also at times the idle speed would surge up and down roughly 300 RPM's while it was at idle in or out of gear, Also it was shaking the vehicle while doing this.

I advised the GMC dealer of everything mentioned above, They test drove it, But it was running somewhat better by then, And they could not feel the little things that I was noticing about how the vehicle was running.

I mentioned to the dealer I thought it might be fuel related like I mentioned in the above post, And they seemed to agree with it, So we just blew it off as bad gas, And once I put the chevron 89 back in, the vehicle has never done it again and runs perfect right now, Hot or cold.

But of course, now I'm starting to second guess that theory after seeing this thread.

I never had any type of service lights come on while it was doing this, And the dealer hooked it up to the computer, But they did not mention seeing anything out of the ordinary.

I just thought I should put my experience out there for all to see as well.

I had read somewhere on here that The GM guys might be reading this forum as well, So I figured I Should say something as well.

My vehicle was definitely falling within some of these symptoms though.

 

A little update, I just got back from Mike Castrucci Chevrolet in Milford Ohio. I was told that they could not do anything since they could not duplicate the issue, well duh!!!!!! I told them it was intermittent and that I couldn't even get the vehicle to duplicate it. I even printed off PO61B TSB and I was told that this didn't apply to my vehicle as I have already had all of the updates. I am starting to wander if the updates aren't the reason for my issue's? I don't remember this issue prior to the install of the updates that were uploaded on my vehicle in March or 2010. I am going back in when they get the new leather for the front seats as well as a new drivers side mirror due to excessive vibration. I am not sure what to do next. How do I bring more attention to this as this is a big safety issue as it has almost caused an accident once. If I don't get a resolution, I will continue to take it in and may have to fight the lemon law on it. Any idea's from forum members? Any and all idea's will be welcome.

 

I have had a wiring harness replace as well do to an intermittent problem, however I have 60,000 in 11 months with no major issues, one great truck. Just drove a dealers 2011 straight Tahoe and the Hybrid has a much nicer feel

 

Hello this is Rodney Brown I am having the same issues jolt then then slowly accelerate. Would you please send me the info soI can share it with my mechanic.

 

it could be a software issue? the dealership can get codes and if you're under 100k miles, it is warrantied.

 

Any updates on the jolting issue? I purchased a used 09 Silverado from the dealer and after about 7 months now it's starting to jolt when coming to a stop or when taking off. Doesn't happen all the time. Took it into dealer and they can't find anything wrong. Starting to notice some other issues as well. Any info??