2005 Passat B5.5 AWX 130 turbo question

[arnieboy]

Hi

I have a 2005 AWX Trendline TDI 130 on 223k miles, which I have had for 10 years. I can't see any history of the turbo ever being changed. I get it serviced by a specialist in Harrow every year. This year I reported under hard acceleration the car sometimes goes into limp mode and I'd added a turbo vane cleaner to try to help but the garage could not replicate the fault. If I switch off the car, it seems fine again and pulls strongly. Lately when going on the motorway, accelerating moderately say 2-3k revs it goes into limp mode. The garage said I might need a new turbo. Before I do so, is there anything to try? I have a basic code reader which shows no codes at all. Do I buy a standard turbo, any recommendations please?

Thanks in advance.

[VAG-Abound]

It's probably worth getting a better code reader to help avoid spending money on the wrong thing. Did the garage not have one that could tell you any relevant codes?

Going into limp mode is often connected with the vanes that you've tried to clean, which usually shows as an overboost code. On one of our similar cars I was able to make the problem go away by driving on the motorway in a relatively low gear each day for a while. The other didn't respond to that so I put a Mellet turbo on to replace the original Garrett.

More recently one of them was very occasionally (when fully loaded with people and luggage) going into limp due to an underboost code, which led to a misaligned boost pipe clip being found. Hard to tell if that is fixed because it happened so rarely.

And it could be an aged actuator not pulling to quite the right position.

[Gazwould]

223K , get a fresh turbo .

[Eugheugh]

Replace all the small silicon rubber vacuum pipes before spending money on a new turbo. My AWX was constantly going into limp until I did this. Better mpg too.

[Crasher]

Old post but my twopence worth, the fault won’t be picked up by a toy code reader, there are two ways this limp mode presents, over or underboost. Overboost is NEARLY always a clogged up turbo and underboost usually a vacuum leak as @Eugheugh alludes to.