Is my turbo faulty?

[Jonny 0101]

:confused: Having had intermittent boost since buying my mark 1 Octy vRS, I recently returned it to the dealer who supposedly cured it with a replacement MAF and throttle body clean. On a recent drive to Wales, the car drove brilliantly with plenty of boost until I stopped at services. The remainding journey saw the car driving well, but the turbo whistle and boost at 2000 rpm had vanished. This was repeated on the return journey. What was also noticeable was that with the current mpg displayed, flooring it in fifth while boosting saw a figure of around 6mpg; while doing this without the boost would see a figure of around 13 mpg.

The car has been back with the dealer for most of last week, and they replaced MAF again, checked all valves/ sensors and turbo, while getting their tuning bloke to check whether it was the remap causing the problem. None of these registered as faulty. I picked the car up today, supposedly cured by replacing a torn breather pipe (y-shaped one). I was shown the offending pipe, with a bloody great rip in it, which I am a little bit sus about, as I'm sure I checked this pipe visually. On driving the car away it was immediately apparent that there was no real turbo noise or pull at 2000rpm, but I couldn't face going back to the dealer again.

This is really bugging me now, to the point where I would happily trade the car in for something 'turboless'. I like the car (a lot), but knowing that it's not always performing as it should makes me feel like I might as well have bought a bog standard car. Can anyone put me out of my misery? What else could cause this? What should the turbo sound and perform like? Would removing a supposedly quality remap cure the problem? Do I need to give the car time to adapt having been fiddled with a lot over the last week?

With a wife in hospital and our first child due in less than 5 weeks, I really don't have the time to look into this issue any more. I want to just enjoy the car not end up loathing it for taking over my life!

Rant over, thankyou for reading and even more thanks if you can offer a solution.

[KenONeill]

Check for someone with VAGCOM / VCDS near you. They'll can check your engine for any faults, even things like lack of boost pressure, and most likely only want a couple of beer tokens for doing it.

[Fugs]

That breather pipe went in my vrs and my brother seat cupra.

This is a very unusual case though!

[Jigger72]

Do you get the EML coming on? If so, the codes would be useful, as Ken says.

Did the garage check the N75 valve? It's a common cause of boost failure which brings on the 'limp mode' and they're prone to failure after a remap. It's only £30 or thereabouts so worth a try. It was happening to me but since fitting a new one no boost problems and no EML.

Otherwise, I assume the garage checked the DV. The Bosch one's are prone to fail as well so a Forge DV might be the answer?

HTH

[skinnyman]

Did the garage check the N75 valve? It's a common cause of boost failure which brings on the 'limp mode' and they're prone to failure after a remap. It's only £30 or thereabouts so worth a try.

I looked into getting an N75 valve and couldn't find one for £30 anywhere! I'm pretty sure thy're over £60 from dealers. If you know where to get them for that price I'd love to know.

[jaymd]

I looked into getting an N75 valve and couldn't find one for £30 anywhere! I'm pretty sure thy're over £60 from dealers. If you know where to get them for that price I'd love to know.

If your nice to me and promise to return it i will send you one that is working as long as you send it back.

[Jigger72]

I looked into getting an N75 valve and couldn't find one for £30 anywhere! I'm pretty sure thy're over £60 from dealers. If you know where to get them for that price I'd love to know.

That's weird. I've just resurrected my old N75 thread and the link to where I bought the valve is:

N75 Valve - Audi TT Coupe and Audi TT Roadster Parts, Accessories, Styling and Performance Tuning

But I could have sworn it was £30ish. Sorry for the bad info, I'll look for the receipt tonight and see why I thought it was £30???

[Lex Dysia]

That's weird. I've just resurrected my old N75 thread and the link to where I bought the valve is:

N75 Valve - Audi TT Coupe and Audi TT Roadster Parts, Accessories, Styling and Performance Tuning

But I could have sworn it was £30ish. Sorry for the bad info, I'll look for the receipt tonight and see why I thought it was £30???

I think prices have shot up recently due to the weakening pound. When I got my N75H in June last year it was something like £32 with the F being about a fiver more

[Jigger72]

Yep – just as I thought. I paid £40, including delivery so they've gone up by 50% over 9 months :eek: