[Audi A3/S3] A3 1.9 TDI (2005) Engine Management Light on after turbo change

[San-]

Last week I had my turbo changed for a heafty price. I got the car back and the turbo kept cutting out at around 65/70mph. (minimal power and drive when it cuts out) Switching the car off and on again seemed to reset the turbo untill you again reached that speed and it drops out again. At this point the Engine Management Light came on.

Diagnostics check showed 3 errors. 1, Mass air flow meter (which I changed but it had no effect as turbo was still cutting out) 2, Pressure Boost Solenoid (or a Thrust Sensor as Audi like to call it) which I canged and seemed to do the trick. 3, Glow plugs which neither me or the mechanic thought should have any effect on the turbo or the light.

After changing the pressure boost sensor the turbo still cut out a couple of times but some reving to get any oil resedue left in turbo pipes sorted that out. Now the car drives fine, but the engine management light can come on again????????

Can anyone help me with why its come back on (when the last diagnostic check showed no errors) and how can I switch it off as the car is driving fine??? Any help would be much appreciated. Thanks.

[shark_90]

If the engine management light is on, then there must be a fault stored. The only way to turn it off is to clear the fault(s).

[SAiLO]

I'd scan the car with VCDS again.

If the engine management light is on then a scan should come back with some errors.

[San-]

Just thought I would update.

I ended up taking it to a different mechanic and he scanned it again, it showed the mass air flow meter again. It turns out the first dodgy mechanic sold me a second hand one that was already faulty. Have since put in a new Mass Airflow meter and switched the light off. It now shows no errors and the light isnt coming on anymore.

[cruiser647]

Does that mean your turbo was changed for no reason? Or was the turbo properly fubared?

[San-]

Yeah I think I got shafted good and proper mate, the turbo did need taking off because the fan had siezed and it was screaming like a mother! But from what av been told, once you have taken the turbo off, you can take out the fan and clean/change it and put your old turbo back on at a fraction of the price!