Query re, MAF sensor and turbo health

[stan]

Just had the 50k service at HWM Audi (walton on Thames). They changed the MAF sensor under warranty. As far as I understand from previous threads a faulty MAF may lead to premature turbo failure. I asked the service manager at HWM Audi about this and he denied that it was a problem.

Can anybody offer any advice/comments ? Is there any way of checking whether the turbos are on the way out ?

I intend to renew the extended Audi warranty when my current one expires in Feb. Does that cover the costs of replacement turbos when they do fail?

Thanks in advance

Stan

[Carps]

I intend to renew the extended Audi warranty when my current one expires in Feb. Does that cover the costs of replacement turbos when they do fail?

The Audi warranty should cover the costs of turbo replacement as long as your car is under 5 years old. The level of cover drastically reduces at 5 years [img]images/graemlins/frown.gif[/img]

[Dippy]

Is there any way of checking whether the turbos are on the way out ?

Non-catastrophic turbo failure starts to become evident through either noise (usually a 'siren'-like noise but also possibly a metallic scraping noise) or oil leaks (blue/black smoke from exhaust) or both. Possibly there will also be loss of power.

Yes a MAF failure can lead to turbo failure, but it all depends on the circumstances. If the MAF is only slightly contaminated, burn will only be slightly lean and this will not lead directly to turbo damage.

Did you notice anything wrong with your car (e.g. low power at high revs) before the dealer diagnosed MAF failure? If not then it is unlikely that your turbos will have suffered.

[philipwalker]

If you know a good garage with a Snap On scanner or vag com kit you can check the boost via block code 115 in the basic settings. This allows you to watch the turbos spin up and the boost is shown in millibars. This will show you if you have a slugish turbo in the early signs of bearing failure

You could ask your local "steeler" with their 1551 to do this....!

[Morpheous]

Measured value block 115 wont check for individual boost, will check total boost via the single sensor on the Tbb.

[philipwalker]

Strange that, I get two readings on channel 3 and 4 via my Snap On scanner, showing m/bars of pressure at block code 115 etc ...You can see the pressure changing as you load and unload the engine. I notice one turbo is very slightly slower to spool up.

[Morpheous]

The readings you are seeing are what the control unit REQUIRES in one zone(depending on throttle position/load etc. The other zone shows what G31, the charge air pressure sensor is detecting from the turbos i.e that all important BOOST.
As there is only one sensor, which is fitted in the TBB where both turbo pipes come together,only a collective reading is possible.

[philipwalker]

Thats good news ...Their I am thinking about changing the turbos....!! The bonus of working in a dealership?? Good having the kit could do with a 1551 cource to work out the readings

[Morpheous]

Yea, if you need any info just drop me a line, I will try to find out the ans.I looked in Block 115 today on a BAM engine. (1.8T-225). Single turbo same two Zones. Hope ive saved you some dosh mate. Lot easier with these mate,no messing around trying to find measured value block info