I have a 2002 Audi Allroad 2.7 with 90K . I'm looking down the barrel of Turbo Replacement or Repair. My Mechanic tells me the waste gate is stuck and that I'm getting "overboost", but he says the only way to "Know" is to dig down to it. 20-25 Hours of shop time!!! He says once I'm there I may as well replace the turbos. So the question I have for this forum is what to do??? The car still seems to run fine, but my mechanic says it's a ticking time bomb. Here are my options as I see them.

1. Do nothing and just keep driving it. ( What could happen??? Ideas Please!!)

1. Tell my mechanic to go for it. Replace both turbos with new turbos. Labor and parts would cost about $5000.00 of course the car is only worth $10,000 on a good day.

2. Sell or trade in the car and be done with it.

3. Keep the car and try and find a less expensive option. I.E. Rebuild the turbos I have, put in aftermarket turbos. ( Ideas Please!!???)

4. Leave the keys in the ignition in a high crime area... (OK that's a Joke..)

Any help is much appreciated....

 

Absolutely get a second opinion. With proper maintenance and good driving habits your turbos should be fine at even 150K--their only wear area are the bearings. I wouldn't trust this guy since the waste gates are repairable without a lot of fuss; I also wonder how both gates failed at the same time. Come on! As far as I know (more a Saab guy but have an allroad) the wastegates are not on the turbos themselves, and are, I believe very accessible. Also, if you had an overboost your car would launch like a rocket, and be basically undriveable. Is it?

Check out eBay for stock replacement turbos; new ones are about $1000 for the pair. Price out a wastegate as well. This engine does not have a reputation for eating turbos or turbo components; sure some people stress them out with hard driving, or after putting a computer chip in, but in general I wouldn't worry about the future.

As an overview, the allroad is a mature design, especially after 01 when the front air struts were improved. Some ZF automatics had failures of the reverse clutch basket, which means no reverse. That too was, I believe, fixed by 02. About the only real gremlins, like all European cars, are electrical, and not too serious. Here's my advice: go to one or two dealers (yes, dealers!) and get their opinions regarding waste gates: symptoms, cost to repair, etc. Then find a solid independent to give his or her opinion and estimate. What area are you in--maybe someone has a recommendation for a good shop. Buono fortuna!

 

The wastegates are cheap and easy to replace. I just got the 710Ns for 50 bucks each and my independent mech installed them for under 1/2 hour shop time each. Just go that way. (and find a new mech, yours sound like a BS artist)

 

They are a good, easy and cheap upgrade, though. Improved reliability and expanded capability for performance mods.

I haven't tried to reach the wastegates on these, but nothing about the turbos looks easy to reach.

The wastegates are controlled by the ECM through a valve. I think it's the N75, which is prone to failure, so you want to have that checked out before you start pulling out engines and buying turbos. It seems more likely to have a single valve failure than simultaneous wastegate failures.

With a VCDS or Vag-Com, there are some data blocks that can be read to figure out what's going on. Requested charge pressure, actual charge pressure, N75 duty cycle, etc. The ECM can use the DVs to limit boost pressure, and the throttle plate is electronically driven to maintain the desired power output, so stuck/failed wastegates could be masked by other engine control actions, resulting in no obvious driveability issues.

There is a study guide for the 2.7t engine that's available on the internet, and it makes a good read. Several systems on the engine are diagrammed and explained, which makes trouble-shooting much easier. The regulation of boost pressure is particularly interesting, since it's more complex than on some other systems. It makes it clear, for instance, why replacing the diverter valves with dump valves will likely cause problems.

If you're going to end up replacing turbos, there are decisions to be made about which ones. The eBay cheap turbos are not known for longevity. K04s are upgrades that offer more capacity, which translates into greater reliability, higher performance potential, or a combination of the two. They cost more, but not a lot more relative to the price of the job.

Is this mechanic familiar with this engine and car? If not, you definitely want to find someone (preferrably an independent) who is. They're not top secret rocket science, but you don't want someone learning on your dime (unless it's you.)

 

if you've had the timing belt job done. If not, and you end up having the engine pulled, make sure they take care of the TB job and valve cover gaskets while it's out. Save you some labor cost vs. doing them separately.

Or you could sell that old junker to me for $4000 cash money and I'll come pick it up!

 

You are talking about Diverter valves not the same as waste gates
dv's control air on the intake side
waste gates control air on the exhaust (how much goes to spin turbo or goes out the exhaust)