MAF or Turbo VW group 1.9TDi (yr 2003) - Crinkly Dave
have run a 2003 110bhp (none-PD) diesel for last year. Intermittent fault, where occasionally it felt like the turbo had ceased to run BUT it was easily cured by stopping and switching off and on, and turbo would reappear. To my mind it was either the MAF or the connection to it (that you have to break when you change the air filter).
As it had 1 year warranty, advised wife to take to Skoda garage, with my suggestion, as warranty would pay (but not for diagnosis).
Skoda agent said computer said MAF or turbo fault, and swopped the MAF for a new one, saying to run it for a couple of weeks, and if it recurred it was the turbo (and they would refit the original MAF)
Just after they did this the problem recurred, as they retested it, and they have now ordered a new turbo, and warranty is willing to pay for parts and labour (but not diagnosis).
Does this sound right. To me, that it got cured by turning ignition on and off pointed to electronic failure, not mechanical

Edited by Dynamic Dave on 24/10/2007 at 22:50

MAF or Turbo VW group 1.9TDi - Screwloose

Spot-on. The reset with the key points to the system dropping to limp-home - something that MAF faults virtually never cause.

What code did they find - 17965? This is a classic fault on the TDi and they've completly messed up on working it through.

Warranty companies are stupid about diagnosis charges. They are now paying for a £1000 turbo job when the fault could be just a piece of perished rubber.

Even in the small proportion of cases that are caused by the turbo; it only needs the vane-ring cleaning. Are they still going to pay if a new turbo doen't cure it?
MAF or Turbo VW group 1.9TDi - Crinkly Dave
That is what is worrying me. Could finish up spending £1000 and still have the fault.
MAF or Turbo VW group 1.9TDi - Screwloose

Ask them what the code was.
MAF or Turbo VW group 1.9TDi - oldtoffee
Brand new turbo for my four year old car for the price of a diagnostic check?

Where do I sign?
MAF or Turbo VW group 1.9TDi (yr 2003) - Bigtone
Had The same problem with my old Audi A4 TDI Changed MAF sensor fault was still there, So i believe the fault was due to the turbo (something to do with the multivane clogging with soot and over boosting?) So hopefully the new turbo will cure your problem.
MAF or Turbo VW group 1.9TDi (yr 2003) - nortones2
It seems such a waste to fit a new turbo, which itself rarely fails AFAIK, when the answer could well be found by a routine check. Other than the MAF, the main culprits on VW seem to be either the vane actuator (vacuum operated, tends to bind and/or be afflicted by pipe leakage) or the EGR! Mind you, what would they care if the wrong thing is "fixed" -if you run out of claim limit its all the same to them!
MAF or Turbo VW group 1.9TDi (yr 2003) - dieselnut
Yes, have to agree Bigtone. Two of my sons have had Passats with the VNT turbo & both suffered intermittently with overboost droping the engine to limp home mode.
The first, I cleaned out the variable vane mechanism which cured the problem.
The second, I was contemplating the same job when the turbo seal blew ( last week).
Since replacing the turbo he has had no further overboost problems.
So yes, it does seem to be a bit of an achilles heel on these engines.
PSA seem to use a different method to control the turbo boost on the Hdi which doesn't seem to cause the same level of problems, judging from the lack of posts on here.
MAF or Turbo VW group 1.9TDi (yr 2003) - Crinkly Dave
Thanks again guys.

I appreciate the thought that my ex-wife will be getting a free turbo at 50k (I am in the North, and we think like that), but if she still has the same problem, are we any further ahead? I can only let it go ahead, and see if they will keep the turbo so I can look for gunge etc. My money is still on something like the connection to the MAF or the crank position sensor, as turning ignition off and on cures it.
MAF or Turbo VW group 1.9TDi (yr 2003) - Screwloose

Neither of those are very likely. The work-through for 17965 [if indeed that is the code?] is quite extensive and mostly [apart from MAP and N75] mechanical checks like split vacuum hoses.

It's a very, very, common scenario.
MAF or Turbo VW group 1.9TDi (yr 2003) - Crinkly Dave
Thanks again, and I accept your superior knowledge and experience here. Best thing I can do is see if I can get the code out of the main agent.
MAF or Turbo VW group 1.9TDi (yr 2003) - Crinkly Dave
Message from dealer today, "will need car for 2-3 days"
OK, more used to traditional diesels, but this is the time taken for engine and gearbox out, not just a turbo change, or does the turbo require this
MAF or Turbo VW group 1.9TDi (yr 2003) - Screwloose

Depending on engine code; book time to replace the turbo is 2.5 hours.

This is, however, a job that can over-run badly if any bolts are.... unco-operative.
MAF or Turbo VW group 1.9TDi (yr 2003) - Crinkly Dave
Thanks Screwloose. I have just spoken to the Skoda service manager, who was very very approachable & did not mind me double checking the fault code.

He confirmed the only fault indicated was "low boost pressure" when the intermittent fault occurred, and they had checked the boost valve and swopped the MAF, and that the fault was indicated during a road test not just in the garage.

I asked if if were possible it was the MAF connection, not the MAF, but he was insistent that the computer checked this out as OK (?)

Will only take a day, but allowing an extra 2 days for Warranty Company to supply a turbo from their own supplier, hinting they would remove the turbo for examination for sticking vanes (I know the VW is a complex variable vane type which doesn't like dirty oil, which is why I change at 9k and not 21k as it has been) and they had "had a few of these". Cleaning the system is something I would do for myself (there is a link on here somewhere), but under the circumstances I would accept the new turbo and 9k oil changes in future.

Thanks again for your help.
MAF or Turbo VW group 1.9TDi (yr 2003) - Screwloose

I do not like the sound of "from their own supplier." There are dozens of cheapo-turbo bodgers around and a warranty company is only concerned with cost.... [Or they would have gone for a genuine one.]

You could well end up with a far worse turbo than the one you've got. The garage can easily check the vane actuator's movement, both by hand to see if it's coked and with a Mityvac to check the actuator.

I'm guessing that the code was 17964 if it was underboost. A much rarer code and one with very different causes. The most common is a failed clip on a intake pipe. There are several joints between the turbo, the intercooler and the engine.

Inevitably; it's the hardest to see that goes - and you virtually never hear it. Ditto a hole or fatigue crack in the intercooler.

As this will likely have a soot trap in the exhaust; a blocking problem there will also affect the turbo boost.

Failure of the N75 turbo control solenoid could be a factor too - but I'd have hoped that they would have already checked that....?
MAF or Turbo VW group 1.9TDi (yr 2003) - rinky-dinky
hi got same prob with my 2004 tdi octavia but mine is over boosting any idea thanks rinky


Edited by Pugugly on 16/04/2009 at 00:46