Hello, ust got my A6 Biturbo, great condition... 6 speed manual transmission.. very fast! but only when it wants to... The car has 113K miles and there is no smoke or knocking at all from the engine, sounds great... very well mantained.

The problem with the turbos:


I always let the car warm up at least 5 minutes befoe using it, then when I start driving I can feel the turbos kicking in as soon as the engine reaches 2700rpm and they work just great! but only on the first 8 minutes of driving, then I just can't fell them. Sometimes all of a sudden they feel like working again and they do for a couple of minutes and then I can't feel them again! VERY ANNOYING.

Another problem, specially in 2nd gear... when the turbos kick in at around 2700rpm you can feel they stop at 3000rpm, then at 3500rpm kick in again, then at 4000rpm they stop, then at 4500 they work etc etc every 500rpm they stop and then work again its the weirdest thing!

Can you guys please tell me whats happening??? Thanks!!

 

Sounds like the car is intermittently going into limp more, or is throttle cutting (throttle cut is when the computer shuts off/decreased throttle input to keep the engine from harming itself - usually seen when a car is making too much boost over what the computer is requesting).

My vote is for limp mode - although could be both with the symptoms you describe. Ok, so:
1. Have codes (if any) pulled from your computer - see what they indicate (post them up)
2. Pressure test intake tract if possible (you'll need a compressor and pressure tester - search a bit for how to make one (its about $5 and a trip to the hardware store)

Once you have the cause we can provide the fix!

 

Thanks I just ordered my vag-com on ebay... once it gets here I will tell you the codes... if any of you guys have any other opinions please post them!

 

A6s don't have to warm up for 5 minutes. Give them 20-30 seconds for the oil to start circulating and then drive conservatively until it warms up. Even in -10o weather in Chicago this winter, I only let it warm up for a minute or so and then drove it slowly until it warmed. You just want to make sure you don't spin the turbos fast when the oil is thick and cold.

If you've run it hard, continue driving for a couple miles to let theturbos cool off to normal temperature.

Five minutes idle is just wasting gas, and these cars get poor mileage to start with.

 

well thats good to know, thank you! but that is not what matters right now if you guys have any ideas on whats going on please let me know! Thanks

 

Have you replaced the stock DVs yet with the upgraded 710n? A cheap insurance at least. Note: you need 2 of these.
http://www.mjmautohaus.com/catalog/p...roducts_id=985

 

I had a similar problem; it may be the coil pack. Check the diagnostics when you get the equipment. I replaced all coils

 

still waiting for my vag-com cable... I will let you guys know thanks for your responses.. so it could be mostly my diverter valves and the coil packs right? whats the symphtom of a bad dv valve?? thanks

 

take it off if its all discolored and gold inside it needs to be replaced ... 113k if they werent replaced b4 they are likely bad

 

DVs could help...
YUO don't have to wait for yuor VAG, start by getting Autozone to chek codes or find a local audi owner (posgt a thread) with a VAG who am sure will be happy to help get codes.

you could very well have a bost leak and it could be in various spots... I assume youdon't have a boost gauge?
I had a similar issue and one of my intercooler hoses was popping off.
Ialso hada leak right behind the TBB before the intake.... though I did not have these symtoms (wasn't a bad leak)