Turbo problem, need advice!

[michaelscott008]

I have a 1999 Passat S 1.9 tdi. A few weeks the car started losing power as if the turbo was cutting out. When I turned the ignition off and then back on again it would start working again. I put it into the VW main dealer this morning to get a diagnostics check done; they’ve said I need a new turbo at a cost of £1126.19. They wouldn’t give me a copy of the diagnostics, because apparently when it’s a mechanical fault there isn’t one. So I don’t know if there’s a fault else where.
There report says:

“loss of power carried out guided fault finding
trace to turbo failing reqs turbo also when
fitting turbo recommended n75 pressure converter
valve due to over boost from turbo”

My knowledge on turbo’s is non existent, does anyone have any advice to how I can dramatically reduce the cost of this problem, as there is no way I can afford that sort of money. I live in the centre on Edinburgh, is there anywhere anyone would recommend to take the car that would be a little easier on the wallet. Or is there anything I can do other than changing the Turbo.

Any help is greatly appreciated!

[bora(ing) nick]

Hya pal.... your turbo is probably fine, and just needs cleaning... It's cutting out because your car is going into limp mode. It's going into limp mode becasue because of overboost / underboost.

I'm no mechanic, but from what i understand, the vanes of the turbo stick. As the turbo spools the vanes move to adjust the amount of boost pressure produced.

Hope this makes sense.

It's a fairly common problem on VW turbos and theres loads of threads on the solutions.

Search for "Limp mode" , and all shall be revealed

Nick

[NICK H]

Even if the turbo is problamatic,it can be repaired/refurbished for much less than a replacement from VW.

As long as you can find someone who can remove the turbo for reasonable cost, then you can send it to a reputable company (such as AR turbo) who will do the nessacery.

That is what I did with mine and I was well pleased with the overall cost and speed of service (3 days from removal from car to refitting repaired unit.)

Only thing is you will be carless for a few days.......

[Frank.A]

Or it could simply be a faulty n75 valve!

This fault is often caused by a vacuum fault,or leaks in the ducting from turbo to intercooler and manifold.

It seems strange that they want to change the valve as well as the turbo.

Why not change the valve first which should be an easy DIY job,and see if it fixes the problem.

Best,
Frank

[ini]

I agree, the fact that they 'also' want to replace the N75 hopefully means that the valve is not working properly, replacing it, and the vac tubes around it may solve your problems.

When a turbo fails, it is generally (but not always) very obvious.

Clouds of grey smoke & 'bad' noises from the compressor wheel milling into the housing + bearing noises.

Black smoke & oil loss into the charge pipes.

Large holes in bonnet and wing where bits of grenading compressor wheel have passed through.

I would get a second opinion, as dealers are prone to selling us expensive parts we dont need.

[michaelscott008]

Thanks to everyone for such good and fast replies!

Apart from the turbo problem the cars running fine, no black smoke or strange noises.

Changing the N75 valve first sounds like a good suggestion.

[scotty33]

Next time it loses power, try unplugging the MAF sensor, as a test. This can also cause no boost, unplugging it makes the car run in limp mode, so there will be a power loss, but the car should drive normally.
Is it 90 or 110hp?

[ronmcintosh]

Hi There
I agree with what the guys are saying, if the turbo had gone you'd certainly be very aware of the fact.
Don't take the car anywhere near a main dealer for work like that, in my own experience in general they havent got a clue. They will just want to shoehorn new parts into your motor as quickly as the can crowbar money out of you.
I've got an A4 with full dealer history and new turbo and Maf fitted (just before i bought it) turned out the car actually needed a 40 quid filter. BUT because the fault didn't show up on a diagnostics test they just started replacing all sorts hoping that one of them would work (sound similar scenario to yours, funny about that lack of printout)

I am just outside Edinburgh and, yes its difficult to find anyone that specialises in VAG at reasonable rates. There is meant to be a really good guy over in Fife somewhere i could try and get some details.
Failing that, switch tack and find someone that specialises in diesel engines. I have a feeling that there used to be someone at the foot of Leith Walk (cant remember name, sorry)

Ron

[chrisvrscrx]

I had problems with my turbo VW said it had gone, I did not believe them and it blew up. I did replace it myself, I got a second hand one off ebay for £250 all the parts came to about £300 (gaskets, bolts etc).

https://www.vwaudiforum.co.uk/forum/s...ead.php?t=9209


Here is the thread with my problems don't wanna scare you but inform you!

[michaelscott008]

It’s the 110hp

I bought the N75 valve from Euro car parts today, will hopefully get it fitted on Monday.
Will let you know how I get on. You never know I might get lucky and get it right first time.

Does anyone know if VW would have had a print out of the fault codes when they did the diagnostics? I asked for a copy when I paid but they told me first, that because of data protection they couldn’t give me a copy. When I kicked up a fuss about it, they then said they don’t print off copies because there trying to be more environmentally friendly. So I asked them if they could email me a copy. The guy went away, came back and said there are no codes when it’s a mechanical fault, so there was nothing he could give me. I suspected at the time he was telling me porky’s. I’m thinking of giving them a call on Monday seeing if I can get a copy out of them, so at least I can maybe trace the fault to a specific part. I did pay £70 after all to be told they would like to extract £1126 out of me.