Problems With Turbo Kicking In

[justmats2]

Can anyone help I have an Audi S2 Avant ABY recently developed intermintant turbo problems. One minute its working the next minute nothing. Any suggestions would be welcome.

[Jamo]

Can you be more specific?

Do you mean boost coming in?

What checks have been done on your car so far?

[justmats2]

Yes sorry.... one minute the boost is there then nothing, not really checked anything at mo as not sure where to start. This has been happening on and off for a couple of months. Car is high mileage (200k). Its hard to say or narrow it down because its so random. More so no boost than boost.

[Jamo]

Could be the knock sensors need replacing.

But start with the basics like replacing the Waste Gate Frequency Valve and having the car Vag-Com to see if it pulls any serious fault codes.

[justmats2]

Thanks for you help got to go out for an hour but any other advice welcome I will leave my computer on

[justmats2]

back again!!! can you explain to me what a vag-com is

[s2 rich]

a vag com is a plug in usually attatched to a laptop which then pulls any fault codes out of your car and tells the operator hopefully what is wrong

[justmats2]

can anyone tell me where i would find the knock sensors located on car ? sorry for coming across abit thick all new 2 me at the mo seems like i got alot to learn !

[T2Andy]

Its next to the super cappasitator and the carbon flux reamyator

[s2dude]

can anyone tell me where i would find the knock sensors located on car ? sorry for coming across abit thick all new 2 me at the mo seems like i got alot to learn !

First things first.
Do a boost leak test.
Search the forum for " pressure test" or pm usern andyp (who sells a good kit) and buy a pressure test kit off him.
then post back when you have done the test

[Rusty]

Boost leak is the best place to start! I had a fiarly massive one when I bought my S2 and it's like someone's slammed the brakes on when trying to boost. All Audi have a test kit, they're in Brislington, just up from the Maccy D's. Alex and Paul ther both own S2s. I'm just north of Bristol if you're really stuck.

Also, get the ECU fault codes read by All Audi and see what's being logged, should give an indication of any sensors that are playing up.

HTH

[ian_jemo]

I have got the same problem as well,

I'm changing my knock sensors today, as long as it don't rain that is.

Thats always the way, you take a week off work and it rains the whole time.

I'll get back to you with the results. I wouldn't think its a boost leak as it sounds like sometimes you are getting a full boost and other times you are getting nothing which is the same as me and I haven't got any boost leaks at all.

Ian

[newsh]

Check that there's not loads of slack in your throttle cable, you have to get WOT to get the ECU to give you the boost. Dont overtighten though. Get someone to sit in the car and floor the pedal and then remove any slack in the cable. Also check you WGFV is plugged in properly, I had this when I first got the car, the plug was half out.

[ian_jemo]

I just fitted the knock sensors onto my car and it has solved the problem.

Drove it for about an hour and it boosted fully every single time. Non of the on off boost I was getting earlier.

Its taken awhile to get my car running right but know that it is, I'm loving it. Thanks to all the help guys couldn't of done it with out you

[justmats2]

thanks for everyones feedback sounds like knock sensors could be the way forward, r they expensive wheres the best place to get them I live in Yate (bs37 - Bristol) any ideas?