So I have a 01 a4 FWD 1.8T, a k03s with 130,600 miles on it. It does these little strange things and I wonder if I should be worried. First, upon a cold start, it will start up, and stumble slightly then be fine. There's a really loud racket coming from what sounds like the oil pan. When you put it into d (it's tiptronic) the transmission gurgles? I'm not sure, but it's making some noise. Every time I come to a stop it dips down to 600-550 rpms before settling in at 800. When I turn the car on in the morning, it smells like lots of gas, and finally, every 4 weeks or so I get a CEL p0411 secondary air injection system. Overall the car is great, but it's these little things that annoy me.

Any suggestions/helpful hints?

 

Likely you have a dying secondary air pump. If you hear the noise at cold start but not when starting it with a warm engine, that's the noise. It's in the corner behind the passenger fog light. Replace it and that issue will be gone.

If you've never seen proof that the transmission fluid has been changed, have it done by someone who knows Audis (it needs to be at temperature and monitored during the change using vagcom). Audi says it's lifetime fluid but it's not.

For the dipping revs, do a seafoam treatment on the vacuum system - it can work wonders. The search feature will turn up two months' worth of reading on the topic. You might also get a new set of spark plugs and throw em in (gap them to .032").

 

+1 to Devil's suggestions. It also might be worth a shot to replace the vac lines too, those have a tendency to crumble over time and a vac leak would explain the dipping revs, slow start and possibly even the gas smell, as a vac leak, iirc, causes the car to run rich.

 

Vac lines are getting done Monday, and I don't think its the pump, because I hear the normal, hairdryer-ish sound every morning. Its, coming from the oil pan, and its a loud rattle, almost like you were shaking a can full of BBs.I'm digging through the records now, (previous owner kept everything from day 1) so far, nothing of a trans flush