2011 Aveo throttle sticking?

[ekelsay]

I have a 2011 Chevy Aveo that has been relatively trouble free since it was purchased until last Wednesday. Last Wednesday after leaving work I was entering the highway, with a speed limit of 70 MPH, and once I got to just over 70 mph I engaged the cruise control. About 5 miles later I came upon a construction zone. I hit my brake to disengage my cruise control and notice that the brake pedal was pretty stiff. The cruise disengaged, but only decelerated slightly.

As I approached the work zone I began to apply the brake. Again, the brake was very stiff and the car seemed as though the cruise was still engaged. At that point I turned the power off to the cruise control, but the car was still going about 65 mph. I then had to use both feet to get the vehicle to slow down to even 55 mph.

Luckily, I was able to get off the highway and onto a service road where I put the car in neutral and rolled to a stop. While I was in neutral the engine revved up to almost 5000 RPM's. I initially shut the engine off then restarted the engine, but it again revved up to about 4000 RPM's. Ultimately, I shut the engine off again and I removed the key and opened the door so all electronics powered off. After letting the car sit for a couple of minutes, I restarted the vehicle and it idled fine. I had no issues with the vehicle the rest of the week; although, I have not used the cruise control since.

However, this morning as I was heading to work and i entered the highway I accelerated to just over 70 MPH and noticed that when I let off the gas the vehicle did not slow down. I tapped the brakes a couple times and determined that the brakes were once again hard to press. I slowly pumped the brakes and the vehicle began to slow down and the brakes began to soften. But when I came to a complete stop I could feel the car trying to inch forward and accelerate. When I put the car in park the RPM's shot up to almost 4000.

A couple weeks ago, my check engine light came on and the guy at Autozone checked the codes for me and said that it was an 02 Sensor that needed to be replaced (downstream). They did not have one in stock, but he said that the downstream 02 sensor was not a big deal and that it was not necessary to replace it right away.

Can anyone give me some guidance as to what my problem might be?

[petrified.rabbit]

You might need to clean your throttle body, I can't say it will 100% fix your issue. You might have a bad TPS or pedal. But it sounds like the throttle plate is getting stuck at WOT, which is somewhere it doesn't go very often.. haha.

I wouldn't do anything with the o2, yet. That is probably/possibly just a symptom of your car dumping fuel while being at "idle"

You might want to check your vacuum lines and check valve to the brakes. WOT does not produce vacuum, so your brakes will get harder to push, but the check valve should hold enough vacuum for you to brake and slow down. Do you have abs?

The is also a slight possibility that you have a bad brake light switch. That would keep the cruise from disengaging. Does your cruise light on the dash work? or is this a DIY cruise?

[ekelsay]

The cruise control appears to be factory installed, but there are no lights indicators on the dashboard indicating when the cruise is on/off. Would the cruise control be an issue since it was not even turned on this morning, and I still had the issue. I have not even turned the cruise control on since Wednesday of last week when the issue first occurred. The car does have ABS. I will check the vacuum lines as well as clean the throttle body and see if that fixes the issue.

[ekelsay]

I found the problem. It was unrelated to the check engine light. The check engine light appears to have been due to two splits in the Fresh Air Intake Hose, but the acceleration issue is due to the gas pedal sticking. I noticed that as I let off the accelerator the pedal would not return to its natural position, but if I pull it up with the top of my foot it would decelerate. I have ordered a new Accelerator Pedal Sensor.

[MetroMPG]

Thanks for the update - let us know if that ultimately fixes it.

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I don't like shops who read a code and then say "it's OK to ignore the light because we read the code and it's not a serious problem."

With the ALWAYS light on, you have no way to tell when some other more serious problem crops up which also sets a code and would also have turned the light on.