01 GAGT surging
 

I just purchased an 01 GAGT that I'm having an issue with. Once it's warm the RPM's like to surge similar to a slipping transmission, especially under moderate to heavy acceleration.

I was having issues with it starting once warm, so I cleaned the MAF and that helped with the hard starting and some of the surging. Still very noticeable in 2nd gear though. I do have an SES light, but it's only throwing a P0420 which I doubt is related to this issue.

Any other recommendations for places to look?

surging how? does the rpms bounce up and down? and do you feel/hear the car go vroom vroom vroom.

mine did that. almost 100% sure it was a torque converter.

The surging kind of feels like a lag-surge-lag-surge-lag-surge, and each lag surge cycle takes about 2 seconds. When it surges it will jump about 500 RPM's. Is this something the upstream O2 sensor would affect, or should I try and find someone with a scantool to take a look at the transmission?

Edit: And I can feel the car accelerate noticeably with each surge. Each cycle feels similar to turbo lag then boost.

I'm not getting a code for it, but it's cheap enough to just throw at the car and see what happens. Thanks man.

yep, good luck.

According to Alldata, that DTC is either bad O2 sensors or a clogged Catalytic converter.

just posting so you i know i'm here