Hey All,

I will do my best to explain this issue as I've had no luck over the years dealing with GM.

I have a 06 LT, with 2.4L and auto transmittion. Sunroof and power everything.
I am having an issue that comes and goes randomly. The dash will beep and then then following list symptoms will happen.

- speedometer and tach both move wildly from the start to finish positions
- computer message center will cycle through display, 'power steering' and 'low fuel' messages
- the theft/security icon lights up on the dash
- sometimes the power steering fails, sometimes it does not
- it feels like the transmission is messing up its shifts, much like if you did a bad shift on a manual, however mine is an automatic
- when accelerating the throttle is very sporadic. it will delay reving and then when it does it revs hard and the transmission clucks the car jerks forward. this happens in an almost pulsing pattern. if you accelerate very gently this is less intense. if you accelerate harder this becomes almost violent
- when slowing down it feels like the transmission is down shifting late and the idles go very low. when coming to a stop its almost like the car continues to accelerate slightly until it finally downshift completely. it will sometimes stall if breaking harder.
-after driving for awhile the throttle and tach will go back to normal and the dash will stop flashing messages, however the transmission and throttle still will act as described above
- sometimes the check engine light comes on, sometimes it does not

Please keep in mind these issues happen randomly. In a half hour drive it will usually happen once. Turning the car off, and waiting a few min will sometimes make it go away. I have had this issue happen years ago and after many times to the dealership they said there was nothing wrong as no codes were being given. It finally took the car completely failing to start for them to see an issue and fix it.

I know there are power steering issues in the cobalts and hhr's however all of the other issues and the fact it is so intermittent leads me to believe it is more of a computer issue(most likely related to the power steering motor).

I realize this is not something I will be able to fix myself however if anyone has heard of or experienced these issues themselves please share any info you may have so I can go to a garage armed with as much info as possible!

THanks again!

 

I'd start the questioning with, how old is your battery? it may just be the cause due to low voltage, my '07 had similar issues at 4 years old, turned out to be a dead cell.

 

Battery was replaced beginning at of this winter. So not even a year old

 

Check the battery cable connection at the battery itself, and under the hood. Also check the ground running to the engine.

and while under the hood, make sure the fuse block is securely plugged into it's receptacle underneath it.

Question: is the Check Engine Light lit on at all?

 

And check the connector at the ECM under the Darth Vader hood in front of the fuse box.

 

thanks for the replies. I will try all these suggestions.

And the check engine light will come on for a bit after the problem happens, but then it usually is gone the next time i start the car. it will also sometimes be one when i start the car but that happens randomly.

 

I would get the codes checked at this point. Even if the light is not on there may be a code in the history that might lead you in the right direction to find your problem.

You can stop by most auto parts stores and get the codes read for free.

If you get codes post then up here and we will try to help.

 

Most people mistakingly think since the Check Engine Light went out that there must be nothing wrong.

 

And then they get mad at the State Emissions inspector.

 

Thanks for the comments guys! Sorry for such a delayed response. Been very busy.

And trust me, I know there is an issue even if the check engine light turns off lol. The issue has been when I have taken it to the GM dealership in the past they said there were no codes being thrown (as of course the check engine light was off by the time I got the vehicle into them) and treated me like a valley girl with no clue about cars. Very frustrating! I have a friend with a code reader and will stop by and see what it tells me as the issue has been happening daily as of late (after about 1/2 hour of driving) and I will keep you posted on what I find.

I've been hesitant to just take it into the dealership without some definite knowledge of the issue as I don't want to be back with the same problem yet again in another year. (This will be the third time the issue has had to been fixed now)

Cheers!