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So, I drove my car on Saturday (1998 A4tq auto) and no issues except the CEL was still on (have a slight exhaust leak, so the O2 sometimes trips the CEL). Go to drive to work yesterday, and the car had a rough idle and almost stalled. Seemed to not make much boost, I can normally hear the turbo by around 2500rpm, I couldn't hear it until around 3500rpm. Go to leave work, and it actually stalls twice and almost stalls two more times. Felt like I had to keep giving it throttle to keep it alive. After it warmed up a bit (I let it idle while I locked up the gate at work), it seemed to be fine. Got home, left the car running, decently smooth idle, VCDS plugged in, just the same code for the O2. Cleared it. Shut the car off, counted to 30, re-started, rough idle. No codes. I was looking at some of the channels, and it seems like it is having to give itself excessive air flow, 10-13 (% or degrees?) of throttle to maintain an idle, then after I rev the engine and let it "warm up" again, it drops to 4-6 (% or degrees?) and has a decent idle again.
Car has 127k on it, as far as I know original O2's. I replaced the 4-pin coolant temp sensor last year or so, just replaced all four plugs & coil packs and the POS a few weeks ago. Also replaced a couple breather lines.
The fact that it behaves itself after it sits and warms up a bit leads me to believe it is a sensor or O2 issue but I'm not sure what values to even look at or what they should be showing in VCDS.
Help please!
Car has 127k on it, as far as I know original O2's. I replaced the 4-pin coolant temp sensor last year or so, just replaced all four plugs & coil packs and the POS a few weeks ago. Also replaced a couple breather lines.
The fact that it behaves itself after it sits and warms up a bit leads me to believe it is a sensor or O2 issue but I'm not sure what values to even look at or what they should be showing in VCDS.
Help please!