need some real advice and help
 

i have 2001 a6 2.7T with 174K miles automatic.
the car has some issues.
CEL comes on from time to time. ill post the code soon
ever since we got the alternator replaced, the volt meter reads more power...often gets stuckk in second gear and doesnt shift (even when i switch it to manual mode or w/e it wouldnt shift)
the window switch keeps blowing (im guessing its the alternator causing it)
the auto seats wont work from time to time- still think its the alternator related

major oil leak. ive been told its the valve cover but got that replaced by the same guy and its still leaking. im thinking of replacing it myself now.

makes a horrible loud blowing noise on cold starts, after a while goes away when the car is warmed up. i think its the secondary air pump?

and the most obvious. loss of power-major loss. its like driving a camry or something.

question is, what are your thoughts on the issues described above. would u say trade in the car (getting appox 2K for it) get something new or keep it till it literally dies. i was reading the mod thread and seems like even with 20K invested this motor doesnt really get more than 600whp- doesnt sound that nice honesty.


the secondary air pump-what is the purpose and can i just pull some fuse or something if it isnt important?

Trans stuck in 2nd gear: Most likely it's going into "limp mode" which is 2nd gear. A fault like that will store at least one trouble code or codes. It is not necessarily the trans that's at fault either. Certain engine faults cause this as well. If the ECM/TCM is missing some data or is getting obviously unplausible data it will put the trans into limp mode to prevent possible trans damage, just as a fail safe. Basically, if you unplugged the trans electrical you'd have Park, Reverse and 2nd gears (and nuetral of course).

Alternator: I'd check the actual charging voltage at the battery using a meter. Check it at idle and 2,000 rpm. Should NEVER go above 14.6 volts. If it does, it means the voltage regulator is faulty (internal to the alternator). In extreme over voltage cases it can cause the ECM to put certain things into fail safe mode (like the trans). There will be voltage over upper limit codes stored.

Oil leak: I'd be willing to bet it's the gaskets under the camshaft adjusters. There's one on the left front and right rear. There's full oil pressure through a passage from the head into the adjusters and they can leak LOTS of oil. It could easily be mistaken for a valve cover gasket leak.

Noise on cold start: It is the secondary air pump. The 2.7L does tend to be noisy, the pump is on the engine, right behind the intake manifold. Good chance one or both of the air injection tubes are broken off (plastic). This is common on high milage vehicles. It will also cause a CEL and trouble code(s). The secondary air is to pump oxygen into the catalysts to get them hot as quickly as possible, for emissions reasons. They don't work until the substrate temp is above approx 600 degrees. If you simply unplug the pump, you WILL have a CEL. If you want to, to eliminate the noise for now, the pump is as I mentioned on the left rear of the intake and has a plug right on top of it with 2 heavy gauge wires. It pulls off very hard, just so you know. Other than the CEL and increased cold engine emissions it won't hurt anything if it isn't working.

Power loss: Many things could cause that. Possibles include puked out turbos, bad turbo recirculating valves, bad wastegate actuators, bad boost pressure sensor..............etc, etc, etc. Also always the possibility the cam timing is way off (which will leave a trouble code and CEL for cam/crank correlation error). Also could be, but highly uncommon, restricted exhaust or intake system. What I'm getting at is, lack of power can be caused by many things or a combination of them.