Uncontrollable Acceleration During Idle

[ThisPartySucks]

A friend of mine has an '09 Aveo, ~68k miles. Her car is sporadically accelerating suddenly while stopped at red lights. Thankfully she has the presence of mind to throw the car into neutral to avoid ramming into the car in front of her.

I've scoured the internet regarding this issue, and although I've found many others who are having this problem, I have yet to find a solution. I'm a car-savvy guy, but I'm perplexed by this issue.

- Spark plugs/boots replaced per the ignition recall
- Throttle body cleaner has been liberally applied
- No visible vacuum leaks
- Problem seems to occur mostly after car has beet sitting for longer periods of time (overnight)

It appears as though the '09 model year does not use a throttle cable, but instead is electronically controlled. Could this issue be caused by a faulty ECM?

Any help is greatly appreciated!

[avguy]

The IACV comes to mind as one likely suspect. But I think I remember reading here that the IAC and TPS can't be swapped out on a 2009, so the entire TB needs to be replaced. I just went to one of the parts sites, and sure enough, they didn't have those 2 valves listed for a 2009. They are available for my 2005, are reasonably easy to change, and not off the charts in price. I don't know if replacement of the entire TB is definitely the only option for a 2009 but, if it is, thanks a bunch guys for figuring out a way to gouge another $100 or more out of the car buying public.

[ThisPartySucks]

I read elsewhere on this forum that the IACV could be suspect, but I honestly couldn't find one anywhere near where the throttle body is. Can anyone confirm whether or not the '09 model year even has one?

[Chevy Customer Svc]

A friend of mine has an '09 Aveo, ~68k miles. Her car is sporadically accelerating suddenly while stopped at red lights. Thankfully she has the presence of mind to throw the car into neutral to avoid ramming into the car in front of her.

I've scoured the internet regarding this issue, and although I've found many others who are having this problem, I have yet to find a solution. I'm a car-savvy guy, but I'm perplexed by this issue.

- Spark plugs/boots replaced per the ignition recall
- Throttle body cleaner has been liberally applied
- No visible vacuum leaks
- Problem seems to occur mostly after car has beet sitting for longer periods of time (overnight)

It appears as though the '09 model year does not use a throttle cable, but instead is electronically controlled. Could this issue be caused by a faulty ECM?

Any help is greatly appreciated!

Hello,

Thank you for your post. I'm sorry to hear you're having these issues with your Aveo. I would be glad to research further but need the last 8-digits of the VIN, current mileage, owner's name and contact number. If so, please private message me at socialmedia@gm.com with Attn: Vanessa in the subject line.

I look forward to your reply.

Vanessa
GM Customer Service

[Thymeclock]

A friend of mine has an '09 Aveo, ~68k miles. Her car is sporadically accelerating suddenly while stopped at red lights. Thankfully she has the presence of mind to throw the car into neutral to avoid ramming into the car in front of her.

I've scoured the internet regarding this issue, and although I've found many others who are having this problem, I have yet to find a solution. I'm a car-savvy guy, but I'm perplexed by this issue.

- Spark plugs/boots replaced per the ignition recall
- Throttle body cleaner has been liberally applied
- No visible vacuum leaks
- Problem seems to occur mostly after car has beet sitting for longer periods of time (overnight)

It appears as though the '09 model year does not use a throttle cable, but instead is electronically controlled. Could this issue be caused by a faulty ECM?

Any help is greatly appreciated!

Check the accelerator pedal itself. It contains an electronic component (AKA 'drive by wire'). My 2009 was diagnosed with a faulty pedal assembly when it was barely new, only two months old. It wasn't doing anything as dramatically weird as yours, but the dealership found it to be defective - so that part can and does go bad.

IMHO, this would be a great car if it didn't have so many cheap, crappy, failure prone electronic components in it.