Turbo Going Tell Tale Signs

[B5DOM]

Are there any tell tale signs that show that the turbo is on the way out, mine is starting to whistle slightly and seems to give a bit of smoke off on start up then clears, plus not sure whether I am used to the car, but I also feel that there is a performance drop.

Is there a simple test that QST could do to tell me then I can take it back to Audi and get it fixed under warranty

[Dippy]

...then I can take it back to Audi and get it fixed under warranty

Don't advertise the fact that it's chipped then... [img]images/graemlins/shocked.gif[/img]

[s2driver]

Yeah. Watch out for hose splits as the turbo will be spinning overtime to try to develop the required boost pressures. KKK units are not rated to very high rotational speeds [img]images/graemlins/mad.gif[/img] .

[s2driver]

I have also seen the results of turbo bearing wear so bad that the impeller chewed the intake 'swirl' and sent loads of metallic particulate into the engine. The reslts were not pretty as you can imagine. White smoke sounds like the beginiing of oil seal failure due to wear. Get it looked at by a specialist as soon as you can.

Lee

[B5DOM]

I purchased the car with the MTM conversion from Gatwick Audi and was told that they would honour the warranty with the conversion as this is how they sold it to me, so fingers crossed.
I Have noticed that when I now turn the engine off there is a hissing noise coming from the engine do you think that could mean a hose split?

[Dippy]

You'd only notice a hissing noise due to an air leak with the engine running.

You will often hear a hissing from the engine bay after turn-off. It lasts a minute or two. I have always assumed it is caused by the air-con.

As you have gathered by now, it is quite possible that you have impending turbo failure, and the cost of the overall repair can vary from about £3K to lots more. If you are still in the dealer's warranty period then you should get it checked out asap.

The S4 is unfortunately not the most rugged engine about, due to a few weak points:
1) Earlier cars (pre MY 00) had turbos with smaller oil lines which could block, expecially if semi- or non-synthetic oil was used, and if cool-down periods were not observed.
2) The TBB (throttle body boot) is flexible plastic (like rubber) and can split.
3) The air hoses can get detached, particularly from the intercoolers.
4) The diverter valves have flexible diaphragms and they tend to split too.

Now since chipping increased boost pressure, the chances of the weak points becoming air leaks is increased. The MTM chip in particular is known to raise boost pressure higher than other chips (although it then tends to be lower than others at higher revs). Now although high boost at high revs is what kills turbos, high boost at any revs is what risks an air leak.

I also agree that you need to have a 'health-check' of your car asap.

[B5DOM]

OK, good and bad news, took car down to QST yesterday and Kim tested the car, and it looks like near side turbo is on the way out.

Then took car to Gatwick Audi for them to look at who informed me that it was prob the manifold!!!!(there was a recal on S4's to replace the manifold) and that they need to do more extensive tests on the car and cannot book it in until end of June.

If it does turn out to be the turbos, [img]images/graemlins/frown.gif[/img] then would they replace both [img]images/graemlins/smile.gif[/img]as surely if one is on the way the second wont be far behind it [img]images/graemlins/mad.gif[/img]

Has anyone gone down this route with Audi "Purchased a modifyed car with 03 turbo's and they are unreliable and want them replacing with 04's for reliability of course, nothing to do with performance". [img]images/graemlins/confused.gif[/img]

Must say Kim is great chap really helpful and that the car will be back soon for Tanoga Short Shift and MTM badging

[JohnW]

I Have noticed that when I now turn the engine off there is a hissing noise coming from the engine do you think that could mean a hose split?

The cars are fitted with an auxiliary electric water pump that runs on after the engine is switched off to circulate water around the system (most late VW/Audi groups cars have these).
If you listen to the 1.8Ts, VR6s, S4s, RS4s, etc they all have them.
Most people only notice the pump when its bearings get noisy and so make it far more noticeable. [img]images/graemlins/wink.gif[/img]

Cheers,
John.

[Dippy]

Then took car to Gatwick Audi for them to look at who informed me that it was prob the manifold!!!!(there was a recal on S4's to replace the manifold) and that they need to do more extensive tests on the car and cannot book it in until end of June.

If it does turn out to be the turbos, [img]images/graemlins/frown.gif[/img] then would they replace both [img]images/graemlins/smile.gif[/img]as surely if one is on the way the second wont be far behind it [img]images/graemlins/mad.gif[/img]

Both changing one or both manifolds, or changing the turbos requires removing the engine, and that's half the cost.

That is NOT the reason why both turbos should be replaced, even if it is true. It is ESSENTIAL that the turbos fitted are a matched pair to ensure that there is a perfect balance between them when the engine is running. So if one is changed then both have to be, even if on old one is reconditioned and matched to a new one (which is a false economy IMO).

Since you're looking at a big cost here, make sure that the dealer has agreed to do it under warranty before negotiating on using K04s. However K04s will not work to their full potential without a remap (not your existing MTM one).

[B5DOM]

We went for a test drive, so that he could hear the whistle, that appears at 4.5 to 5k revs.

Then went back to the workshop and I peered through the window and saw them attach an electronic machine somewhere in the back seat and then some tube type things in the bonnet which I believe was to test the air flow meter.(As you can tell I am not that technical!) [img]images/graemlins/quote.gif[/img]

[B5DOM]

Since you're looking at a big cost here, make sure that the dealer has agreed to do it under warranty before negotiating on using K04s. However K04s will not work to their full potential without a remap (not your existing MTM one).

That is what I am gathering the info for at the moment, to try and get the dealer to install the o4's on reliability issues rather than performance as they sold me the tuned car in the first place!

Kim said that if I can get the O4's on warranty then I can take the car back down to him to do the rest of the MTM370 Upgrade which I believe is just the remap

[Nige_RS4]

Whilst you have the engine out, replace the down pipes with Milltek or similar - save a small fortune later and good for 20+bhp, faster spool-up etc... [img]images/graemlins/thumbs.gif[/img]