Upstream O2 sensor

[starcruiserinaz]

Hello all:
I replaced my upstream o2 sensor with an OEM style unit. Now my car is revving up at down mainly when using my AC. Any ideas which sensor could be causing this? TPS? Do I need to replace, or can I try cleaning the TB? 2006 Aveo sedan.

[avguy]

Why did you replace the O2 sensor? Was there a code that you were trying to get rid of, and how was it running before the O2 was replaced? Any up and down rev before the new O2?

[starcruiserinaz]

Hi Thanks for your reply,

Yes there was a code that indicated that the upstream o2 sensor was in need of replacement, plus the element was shorted out too. It ran very rough before the sensor replacement. It runs smooth as long as there is no load put on the engine A/C power steering. I did find a cracked vacuum line which I repaired. So the only thing I can think of is the Throttle Position Sensor since I'm not getting anymore codes.

[avguy]

if it had been running badly for a long time, I'd be somewhat concerned that the cat has become plugged. But performance problem diagnosis normally beginss with the plugs and wires. How long since they were replaced, and what type are installed? Have you removed them to check how they look?

[starcruiserinaz]

iridium plugs are new, wires too. Car is pretty well taken care of. Just curious if anyone has had a similar experience. I ve seen this happen to VW's. Aveos are not so technical.

[avguy]

Cleaning the TB is never a bad idea, just use sensor-safe cleaner. You might want to check the very small bent tube connecting the MAP sensor. IIRC another guy also living in a hot climate posted this line had cracked, but the split was very small and couldn't be seen until he examined it up close.

[xintersecty]

I just found out my intake line between the filter and TB was cracked too. check there. You will need to take it off.


That can be leaking causing a performance issue too.

[starcruiserinaz]

Wow, that look expensive. After driving the car around everything seemed to have went back to normal. I was not aware that these TBS had to re-calibrate. Like I said previously, I've seen this happen to VW's, but would not expect this on an Aveo. Learn something new. Thanks for your help!