Just bought a 2000 A6 2.7T last month (private sale).

Been going well till I took it to 200km/h yesterday when a sudden power loss occurred. Has stayed like that ever since.

The engine is still revving fine and seems mechanically ok (I am no mechanic so could be way off here). Gears still work fine and car drives the same for cruising around. It feels like the turbos are not working anymore. I had a look under the hood and noticed one of the clips holding the large flexible pipe that feeds the turbos was missing. Cable tied it for now, but still no power. Tried to check all the hoses etc but didn't see anything else obvious.

Any ideas on what to check and what can be done with DIY? What kind of things generally go wrong?

 

It really does sound like turbo loss. The likely culprit on the 2.7T is usually the throttle body boot which is the "Y" shaped boot just before the intake. Very difficult to physically see any leaks or cracks in the boot. I made up a device out of ABS plumbing materials that connects to the the intake manifold from the filter. Then add pressure from an air compressor of not more than 10 PSI and found the leak easily then.

 

Yeah, definitely sounds like you are in limp mode. Had this happen a couple of times in the last little while. Here is a DIY for building your own pressure tester. You will need an air compressor though.

http://www.awe-tuning.com/media/pdf/...ure_tester.pdf

On a side note gotta give a shout out to Ryan (Nothing77) for helping me out both times with this.
Never thought a silicone hose would tear the way mine had...All better now though!

 

Thanks guys for the advice.

Will check it out asap.

 

Almost forgot - how urgent is this?

Obviously the drive quality is down, but I mean from a preventing further damage perspective? Is driving the car in this state likely to cause other failures?

 

Very urgent, if you have a large boost leak, the turbos will try and achieve desired boost, this results in severely overspun turbos.

 

Ok - now I'm worried...

Tried my luck looking for visible tears, but didn't find anything.

Found someone selling a Chinese clone VAG which I am considering buying to get the codes asap. Is this a bad idea? Horror stories using non original VAG?

 

Before you go and purchase a VAG COM you should take the above advise and for $20 make a tester and follow the directions. I couldn't physically see the tear on my 2.7T boot either but was able to readily identify it once I put some air pressure into the system. A rip at the bottom of the throttle body boot is a common thing and is quite easy to repair yourself.

 

Any instrument/trouble lights on? Check to see if your brake lights work. Sounds like a limp mode for sure.

 

Got a VAG last night cos I want to see what's going on myself instead of having to take it to the workshop every time something goes wrong. Will still make the air pressure tester to check the hoses etc.

There are no instrument lights on, I'll check the brake lights soon.

Found this fault code:
17125 - Torque Converter Clutch: Stuck OFF / No Power being transferred
P0741 - 35-10 - - - Intermittent

How bad is it?