Stalls on slow sharp turn.

[Mrs Homer]

Having a small problem that I want to figure out. Just recently our 03 Envoy will stall on a sharp turn. Mostly backing up and not all the time. Some of my research suggests there is a sensor that tells the engine to increase power when under a load. Does any one know where I can find that sensor? ( the article said it was in the powersteering some where)

The other thing, I'm questioning is if maybe this is the cause: We recently blew the rear end out of it and the battery was disconnected during the change. I know the computer reset it's self and although the engine wasn't rolling etc (like in the past) is it possible the throttle body needs cleaning again (that worked in the past to clear it up) and how often should the throttle body be cleaned?

 

[littleblazer]

It's very possible the throttle body needs to be cleaned. I do mine once a year, it's usually close to spotless though. When you put the steering to lock, full turn, it should do a little surge slight drop in rpm followed by it coming up some. Any time the battery is disconnected it is recommended to clean the throttle body. You could pull off the resonator and open it and look at it with a flashlight and if it looks grimy that is more then likely the isssue. It sound like it to me from what you describe anyway.

 

[Tiggerr]

I'd clean the TB again. That said it could be your rack starting to go too, or ps pump. If it's building too much pressure is could be bogging down the motor by overloading the pump. Not too likey but possible. More than likey a good TB cleaning should clear it up hopefully. I usually do mine twice a year just to keep it from getting too nasty.

 

[Mrs Homer]

the rack was replaced just over a year ago so I'm leaning toward the TB. Thanks guys, I know we also have to replace the valve cover gaskets (leaking) and so it wouldn't surprise me if it just all needs a damn good clean up.

 

[Tiggerr]

the rack was replaced just over a year ago so I'm leaning toward the TB. Thanks guys, I know we also have to replace the valve cover gaskets (leaking) and so it wouldn't surprise me if it just all needs a damn good clean up.

Cleaning TB is easy/cheap. Good place to start anyway. Be sure to disconnect battery for 30 minutes or so to reset PCM.

 

[nozzleman]

Timing is everything!
Same problem only different.
Changed the thermostat a couple weeks ago. Reconnected the battery to reset the ECM and had the same stalling symptom when I had the air conditioner turned on. Baffled, I re did the battery connection. Same symptom, it stalled pulling into my work parking place or when slowing early for a stop sign or sitting at a light. Always with the air on. With the air off, it runs very well. Took it to my trusted mechanic shop who changed the MAF sensor and told me that the Throttle Body is worn and needs replacing. I was skeptical until reading this thread. My wrench friend knows that I like to do some repairs on my own and I think he was hinting that I could replace the TB myself, in that he didn't just put one on.
It's not that difficult , is it?

 

[Tiggerr]

Timing is everything!
Same problem only different.
Changed the thermostat a couple weeks ago. Reconnected the battery to reset the ECM and had the same stalling symptom when I had the air conditioner turned on. Baffled, I re did the battery connection. Same symptom, it stalled pulling into my work parking place or when slowing early for a stop sign or sitting at a light. Always with the air on. With the air off, it runs very well. Took it to my trusted mechanic shop who changed the MAF sensor and told me that the Throttle Body is worn and needs replacing. I was skeptical until reading this thread. My wrench friend knows that I like to do some repairs on my own and I think he was hinting that I could replace the TB myself, in that he didn't just put one on.
It's not that difficult , is it?

Not difficult at all. Pull the resonator and the hose going to airbox and its right there. There's a video on YouTube I'm sure. I wouldn't replace it I'd clean it and see. Doubt you needed a MAF either.

BTW....You have to remove the TB and clean the back side of it and the butterfly. Cleaning just the front won't cut it. I just use regular old carb cleaner on mine. No problems. That MAF cleaner and TB cleaner doesn't cut the gunk nearly as well.

 

[nozzleman]

Thanks for the quick reply . I'll get right on it!

 

[stickypoop]

Mine does this too. It's happened frequently both before and after I cleaned the throttle body. Reverse, close to full lock and almost dies out. A few times I was sure it did stall but a quick tap on the throttle and it grabs again and keeps purring along. My PS pump groans a lot. So for me, I'm guessing that's my gremlin.

 

[Texan]

Poop, I would recommend that you change/flush
your PS fluid.

 

[nozzleman]

"Not difficult at all. Pull the resonator and the hose going to airbox and its right there. There's a video on YouTube I'm sure. I wouldn't replace it I'd clean it and see. Doubt you needed a MAF either.

BTW....You have to remove the TB and clean the back side of it and the butterfly. Cleaning just the front won't cut it. I just use regular old carb cleaner on mine. No problems. That MAF cleaner and TB cleaner doesn't cut the gunk nearly as well."

So I didn't get "right" on it.
What a difference cleaning does. I wouldn't have thought that just cleaning a little residue off of the butterfly and barrel would make such a dramatic difference. Oh, cleaned out the vacuum passage too. Put it back together and idle went up to 2500 RPM. Had to clear the ECM which restored everything back to normal. Runs like it was new.
Thanks for the help.

 

[Tiggerr]

So I didn't get "right" on it.

What a difference cleaning does. I wouldn't have thought that just cleaning a little residue off of the butterfly and barrel would make such a dramatic difference. Oh, cleaned out the vacuum passage too. Put it back together and idle went up to 2500 RPM. Had to clear the ECM which restored everything back to normal. Runs like it was new.
Thanks for the help.

That's what we're here for. Glad it worked out!