I have a 00 2.7t (automatic)

Symptoms:

* When slowing down, it seems like the brakes engage quickly then let off (thought it may be a rough shift but tried in tiptronic and does not happen in mid shift.)

* The rpm's seem a little erratic lately, specially when i slow down to a stop, the rpms well drop to abou 500 rpms momentarily jumping the car forward and then settling back at about 750 rpms within a half a second.

Known problems:

* Secondary Air injection b1 and b2, I can't see this causing the problem because from what I understand all it does is warm up the catalyst converter in cold weather starts

* b1 s1 O2 sensor intermittent low resistance, I could maybe see this causing the problem because it does effect the fuel to air ratio but I have had this fault code for a couple months now.

* A/C pressure switch fault code, my A/C seems to work fine so I'm not horrible worried about that fault code unless you guys can think of some relevance

I do have a Ross-tech Vag-com with the full license, those are the only fault codes that are kicking out, I do run the auto scan every couple days just to see if anything else comes about.

Any ideas? Anything I can try with my Vag-com to help diagnose? And I do plan on replacing the b1s1 o2 sensor asap and probly clean my MAF to see if that helps at all.

 

My car actually stalled today when i had to stop quickly, if i drive very cautiously there isn't much of a problem but it almost seems like the transmission isn't keeping up with the engine?

Any input would be appreciated.