[DrivenDaily]

Quick question or two...

Did you spray cleaner into the TB and then wipe it down, or did you spray the rag and then wipe the TB?

This revving when coming to a stop: Is the engine already at 3ooo as you're slowing down, or is it slowing as you do and then suddenly revs up to 3ooo?

The reason for the first question is that the motor that moves the throttle plate is in that little chamber with the plug. If any cleaner got inside there, it could have caused issues with the motor. I'm not sure if the motor is available separately or if you'd have to replace the whole TB, but the whole TB is most likely.

My thinking behind the second question is that the learned behavior of the TB can't be reset with the same tricks you tried, although those were intelligent things to try. Kudos. I had my TB cleaned by a dealer tech that I visited back in 2019. After cleaning it, he hooked up his computer and had to go to a specific property and manually set it to zero. Over time, the ECM will adjust the action of the TB due to build-up on the butterfly and/or throat. When you clean it, it doesn't know that so it will move the throttle to the learned position. This could explain the wild revving and jerking. I'm not sure if it can explain the PO171 or not.

 

[DrivenDaily]

Yes, unfortunately I sprayed the cleaner directly into the TB (just like I saw A bunch of people doing in videos 🤦🏻‍♀️) it wasn’t until trying to trouble shoot that I came across that tinyyyy little detail that seems to make or break or you.
The revving and jumping up to 3k will happen while I’m driving at higher speeds then coming to a stop (so yes, I was originally at higher rpms) and also if I’m going slower like in my neighborhood and it’ll jump up to 2k or 2500 at a stop.
From what I’ve researched gm made this throttle body and tb sensor as one unit. Apparently you use to be able to replace the sensor by itself but with this 2011 you have to by a complete new unit (of course, eyeroll). I heard that when people replace the brand new throttle body/sensor that they have to end up taking it somewhere to do a relearn anyways. I would hate to pay for them to attempt it on this one only for the sensor to be the problem and it can’t be done. Then have to pay for a new throttle body and another relearn. I’m so mad that I even ended up doing this now. This is one of the easiest things to do as far as accessibility and time but it has caused me the most problems and time afterwards.

btw for anyone who might be reading in the future with the same problem: this make and model, 2011 Malibu, doesn’t have a idle air control valve. I read lots of suggestions about this that might be a problem and may need to be cleaned only to realize my car doesn’t have one.

We've all learned lessons the hard way at times. Sorry this was how you learned it.

When DBW (drive by wire) replaced the throttle cable, it also replaced the IAC valve. I'm just glad mine doesn't have EGR!

Shop around the dealers and see if you can befriend a tech. It's a very simple process that takes very little time. He/She just might accept a decent dinner or some of their favorite brew-skis, and you'll have gained an invaluable resource for the future!

 

[DrivenDaily]

When you return, hopefully another scan will be covered by your earlier work. It would also be nice if it all works right from now on.