Looking for advice on turbo related problem

[jay85]

Hi,

So recently my car (Audi A4 2.0 TDI) was suffering from Limp mode and puffs of smoke coming out of the exhaust.

This turned out to be a faulty EGR valve that was not closing properly. I have replaced the EGR valve and the car is now back to normal again....almost.

It now drives normal for about 10 mins and then goes into Limp mode, no smoke this time. (restarting the engine resets the limp mode) I had the codes read and got P0234 -Turbo boost limit exceeded.

I'm hoping the turbo isn't broken (it feels like its working before it goes into Limp).

My (wishful) thinking is that the EGR valve failure (and smoke) could have resulted in the Turbo getting dirty and it just needs a clean.

Can anyone advise on this, or had similar experience?

Thanks,

Dave

[generationx]

My Mk5 Golf GT TDI 170 (same engine?) used to do exactly the same, albeit less frequently and usually after a fairly specific set of driver inputs. The fault code reader at the local Volkswagen dealer gave the same "excess boost" code.

After a bit of searching around I came to the conclusion that the likely culprit wass a dirty/sticking wastegate, but as I sold the car soon after I never got round to doing anything about it.

So to sum up; turbo and/or wastegate rebuild?

[jay85]

Thanks, I'll look into cleaning the turbo.

Just looked up the price of a replacement Turbo - Flipping heck, they're expensive!

[GreenV8S]

jay85 said:

I'll look into cleaning the turbo.

Don't you mean wastegate?

[finlo]

GreenV8S said:

Don't you mean wastegate?

Variable vanes are probably sooted up, very common on vag stuff.