A3 TDI turbo problems

[GarryA3]

Been having problems for a while with the boost on my car.Had the MAF changed and just had another valve (possibly diverter) changed and it seems to be driving better but on occasion when i reach 3000 revs its feels like it is jumping into limp mode because i feel the boost go and it doesnt drive right untill i turn off the engine,then back on again.
Ive had it checked again and the code that is coming up is the turbo.
I remember VAGMAN enquiring about the cleaning of the turbo due to the vains of it being clogged and sticking open but ive been told there are certain parts of the turbo you cant access.
Does it sound like a new turbo is required to anyone?If so,what kinda price would i be looking at?


VAGMAN-if you read this any info on how you got on would be appreciated.

And i read the post about the 1.8 A3 turbo but i think my problems are different,which is why ive started a new thread.

 

[The Slug]

Out of interest, what mileage has it done and has it had a remap? Ta

 

[GarryA3]

58,000 mate and its a 2001 Y plate.No remap either.Ive been told roughly £500 just for the turbo but i want to be 100% sure its that before i commit to anything.

 

[VAGMAN1]

Hi Gary

Sounds like EXACTLY what I had. Have you had a full diagnostic on the turbo system, whereby the operation of each part of the turbo system is checked? I had this done at my local dealer - £70 well spent because it isolated the fault........which was unfortunately the turbo vanes clogging open.

What happens to the turbo on a TDI (after quite a few thousand miles) is that bearings on which the fans run (via one long shaft) are subject to wear, causing wobble. Even though it may be fractional wear, the fans go at such high speed they cause the shaft to wobble, which in turns allows oil to mist out from the oil chambe of the turbo, past the oil seals and into the exhaust inlet/outlet. This oil then mixes with soot to form a paste which coats everything, including the variable vanes (which control boost). In my case it was happening almost exactly 20-25 minutes after a cold start - turns out once the car was to optimum temp the paste would be just the right thickness to cause the vanes to stick open when accelerating. This in turn causes overboost and the ECU shuts the turbo down hence putting the car into limp mode.

I went down the road of refurb, as you get a trubo as good as new and you know it will bolt straight on. My refurb cost £258 from a local engine centre and plus new gaskets and seals all in cost was around £300.

If you want more info then let me know, but I'm afraid it's almost certainly a turbo and only thing you can do is get it replaced or refurbed.

oh and btw is anyone else fed up with the fact that so many garages tell you it's the MAF when ever you experience power loss and hey presto you're £100 or so poorer with no fix!

 

[GarryA3]

Thanks VAGMAN.
Can the full diagnostics check on the turbo be done using VAG-COM?I dont know about these things but the guy i use for my repairs has told me to go to someone with VAG-COM because the instrument he uses isnt as good.Or would i have to take it into my local stealer??

 

[VAGMAN1]

I don't honestly know if VAG-COM can run such a check on the check. I'm sure it can, but it's finding someone. The reason why i went to a dealer to get it done was because they had to put it in writing as to what was wrong, so if my fix didn't work then I'd be back at the dealers asking awkward questions!

I know a VW dealer can perform the same check, so may be worth comparing prices between local Audi and Vw dealers.

btw what type TDI have you got?

 

[GarryA3]

1.9 TDi 110 bhp.Nothing more than a basic tdi but ive had alot of problems with it.Ive been having this bother for over a year now and, as i said, had the MAF changed and another valve.It is driving a bit better but because i still have this problem im wondering if its been the turbo all along.

 

[VAGMAN1]

So other than the MAF/turbo, what other problems have you had?

As I said before, just save yourself alot of guesswork and get a full diagnostic done at either a dealer or specialist, but I would say it's almost certainly your turbo clogged up.

What mileage has the car done? Mine started playing up around 147K.

 

[chrisb]

[ QUOTE ]

oh and btw is anyone else fed up with the fact that so many garages tell you it's the MAF when ever you experience power loss and hey presto you're £100 or so poorer with no fix!

[/ QUOTE ]

The problem is, so many garages will just swap bits rather than work out what is wrong (probably because they have no idea what is wrong), and the MAF is the automatic thing most try if you have a TDi with bad performance. It's a bit more complicated than that! If you have VAG-COM there's a test procedure you can use to see if the MAF is OK.