Cleaning Throttle Body

Hello everyone! I recently tried cleaning the Throttle Body on my 2007 Aveo LS. It's got 93,000 miles. The check engine light was on with the P2135 code. Just a little background, I bought the car used a year ago and have recently learned more about cars than I ever though I would because of all the issues it's been having. The car was stalling soon after purchase while idling especially during cold weather. The air intake hose was broken and I replaced it with no resolution of the stalling. It also had a rough idle.

Finally about a month ago the check engine light came on and I watched several youtube videos on how to clean the throttle body. Most of the videos suggested turning the key to the on position with the engine off and having an assistant press on the gas to open the throttle body to clean it. When I did that, the throttle plate barely opened up. I was still able to get some cleaning done since it was extremely dirty and it actually resolved the check engine light, the idling seems less rough, the car is more responsive to the gas pedal, and so far.. no stalling over the last 4 days (fingers crossed).

Has anyone else had this issue, of the throttle plate barely opening during cleaning? Should I remove the throttle body and clean it better out of the car?

Hey Darwin, yes they can get pretty crusty on the backside of the butterfly valve. I found it easiest to remove the TB assembly, 4 nuts and a couple connectors and some hoses should have it off so you can get all the stuff caked on the back side from the PCV valve. These are always a mess on most cars, once clean it should eliminate the codes and idle issues. That oil vapor makes a nasty mess over time and sticks things up.

On these later 'fly by wire' throttle setups the ECU controls when to open the throttle, so bench cleaning is the best way, and least hassle. Pretty common on anything 06 and newer these days.

Thank 06T200! Do you know if there is anything connected on the aveo throttle body that might leak during removal, like coolant?

you might loose a little coolant , also use throttle body cleaner and not carb. cleaner also check up your air idle. control valve that will gunk up also thats on the throttle body as well.

After 140 thousand miles, you should have seen the dirt on the intake headers. I know as I have mine off for a head job. It's easier with it removed.

I have some hesitation and a check engine light, maybe I should give this a go. Any ideas?

If the TB is extremely dirty, you should remove it from the engine bay as you'll just be depositing all the crap you blew off the TB into the intake manifold.

Also consider changing plugs and wires if they haven't been replace recently.

Also, look into "Seafoaming" the engine. It can make a nice improvement if the engine was neglected for a long period of time.

Didn't remove my TB, but it wasn't too bad. I used TB cleaner, and a tooth brush.