Turbo problem - lack of boost

[RS2_freak]

I've literally just come back in from a short drive. After pulling out of a petrol station (easily) I accelerated (not violently) but I could tell something was up as the normal boost simply wasn't there.

I drove it home and, while you can tell there is some turbo influence at higher revs, its simply noting like it was. I was reluctant to give it any stick for fear of further problems.

I've only had my car a few weeks so am very much still learning. Its fresh out of a service at Fontain and all was well then. Any ideas what it could be?

[Rob20vurq]

Possible boost frquency valve.
You are going to have to buy vagcom programme and cable. Its a big help in finding any faults, just plugs into your fuse box and tells you any logged fault codes.
Or Mr Audi dealers will read the codes for you then bend you over and pull your pants down for the privilage!

I have worked on an RS2 that had come from Fontain, I wasn't impressed.

Hope this helps,

[RS2_freak]

Thanks Rob.

I bought my car privately - two owners and a full service history with every receipt (something I'm keen to maintain as I'm a bit of a perfectionist when it comes to keeping my car).

Fontain is not far from where I live, so I had them inspect it before buying and then service the car last week. Its also just sailed through an MoT.

Any pointers where I can get one of the vagcomm units?

[Rob20vurq]

ebay.com for a com lead. you need the one with two little plugs, one white, one black.
You can download a shareware version on rosstech.com. it gets the codes ok, you don't get translation as to what the code means, but you can get a list from s2forum.

Rob

[RS2_freak]

Excellent! Thanks!

[clived]

Have you done the obvious and checked you don't have a loose boost pipe anywhere?

[AAH!]

I agree with clived check for boost leaks first.

If you want to go the poor mans VAGCOM route you can pull the blink codes from the ECU with just a 12vLED (from Maplins) and a paper clip. It worked for me and is fairly straightforward and you can check nearly all the ECU sensors for faults. VAGCOM is easier though.

http://www.s2central.net/blinkcodes.html

http://www.s2central.net/


Also have a good look through this site - although not specifically for RS2's much of the info is relevant as it is essentially the same engine :

http://www.sjmautotechnik.com/trouble_s ... boost.html

http://www.sjmautotechnik.com/trouble_s ... .html#fcs4

Do an output test - this tests the electrical solenoids like the Waste Gate frequency Valve (controls boost)
http://www.sjmautotechnik.com/trouble_s ... html#outs3

More info here:

http://www.s2-audi.co.uk/

http://www.s2-audi.co.uk/tech_articles/ ... faults.htm

There is a ton of info on all the above mentioned sites and if you use the search facility on this site and the www.s2forum.com and do a bit of cross referencing you may get to the bottom of your boost problem and if you don't you will have learnt a lot about your car trying.

Hope this helps .... Angus

[alastairg]

WGFV/N75 check it (with vagcom you can do a specific test) Check all connections (mine had a worn wire due to it being up against the headlight rear plastic cover).
If in doubt just replace or remove and spray/soak in WD40

[alastairg]

Is it better ?

[RS2_freak]

Thanks for the advice guys.

Quick update. A mate's mate is an ex-VW mechanic and had a VAGCOM. He gave it a check, but nothing showed. We did however replace a small vacuum pipe which had a split end and turbo boost came back.

However, I'm still not 100% convinced its how it should be. Before the turbo really did kick in and launch. Now its seems too smooth and sometimes the boost seems better than others. Plus I don't think its consistent as to what revs it kicks in - suspect another air leak or the airflow meter.

Anyway, booked into QST for a diagnostic Friday next week.

[dsbonney]

can anyone tell me the correct way for n75 frequency valve to be fitted?
thanks