No boost, some help please

[S3 Nattie]

Hi guys, come for a little advise please. My car has been running really sluggish over the past 2 weeks. I can hear the turbo spooling and the DV whooshing when it should but it has very little power, cars runs fine though.

I replaced my DV recently with a standard one and cleaned my throttle body and MAF sensor as I had a misfire, which it sorted out.

Recently bought VAGCOM and had a N249 Valve mechanical malfunction fault came up. I deleted the error and it hasnt come back up since although car still runs really sluggish. The car feels like it has no boost or turbo.

Recorded MAF results in 4th gear from 2000rpm to redline and had a maximum of 169.19 @ 5760 rpm, which seems about right for a standard 210 S3 although when I unplugged it the car runs exactly the same. When I recorded my pressure figures ( think im doing it right, block 8) im getting 80.0 mbar @ 2000rpm and 180 mbar at the top of the rev range. My mbar figure are 80.0 and 85.0 mbar for most of the rev range. Is it me or are these figures really low

I have checked all the hoses and they all seems to be ok and secure. Replaced the breather pipe which goes to the TIP as it was really soft. going down the garage now to get it up on the ramps to have a really good look at the hoses underneath but they do all seem to be alright.

I have checked the T piece on the N249 and it seems to be ok. Not to sure what to do now. Any help will be great thanks.

Nathan

 

[S3 HODGE]

Does the DV "Whoosh" louder now its sluggish? Maybe a boost leak....

 

[S3 Nattie]

Um not really, sounds the same as when I got it. The one I had on it before used to flutter so I replaced it with another standard one and it has sounded the same ever since

 

[Shy19s]

This happend to a mate of mine on his evo 6 - cracked turbo housing.. have you checked that side of things?

 

[MintyS3]

If there was a fault reported I would start by replacing the N249.

 

[S3 Nattie]

Well just come back from the garage and all the pipes are ok. Havent really looked a the turbo. It was running really strong few weeks ago. If the turbo was on its way out wouldnt it be a gradual thing.

I was thinking about replacing the N249 valve, the error code has not come back up. I understand that the N249 valve is what helps the DV function properly but would it make my pressure values that low.

What should a standard 210 pressure values be.

 

[Shy19s]

mate if the turbo cracks it could happen all at once, not nessisarily gradual, we were on boost fine one minute and suddenly the next time it spooled up not as quick, but making all the same noises.

Anyway, hope you find the problem.

 

[S3 Nattie]

Thanks for the advise shy. What is the best way to check the turbo with it on the vehicle

 

[S3Steve]

Wouldnt replace the n249 unless the fault code comes back mate, you often get the n249 flagged up when the dv is u/s (such as the fluttering symptoms youve described)

 

[S3 Nattie]

Well I was going to replace it if the error came back but it hasn't as of yet. I changed my DV about three weeks ago as it was fluttering and reset the ECU by removing the negative on the battery. I am stumped why my pressure readings are so low. What sort of pressure in mbar should I be getting and is there anything else I could do with the shareware version of VAGCOM.

 

[S3 Nattie]

Does anyone think my loss in performance could be down to a temperature sensor as it is quite hesitant and revs are quite high (1500-1800) in the mornings for few minutes

 

[S3 Nattie]

Anyone ?

 

[fran-s3]

Dude you could be forever changing and swapping bits unders the sun - don't waste the time, cash and effort. Take it to a proper Audi specialist (and I dont neccerally mean an Audi dealer!) who'll be able to diagnose it for you. Whereabouts you based? Sure memebers close by will be able to advise on a good one.

 

[Dani_B19]

Have you taken the TB off and gave it aclean, if all else fails then take it to a reliable garage and get them to check the turbo.

 

[S3 Nattie]

Well im based in Cardiff and only know of one specialist in Cardiff called NG motors if anyone has heard of them. Ye going to book it in for them to have a look, been on here searching all sorts of things and dont seem to be getting anywhere lol Thanks though for the advise

 

[h100vw]

You should log boost and MAF then go from there.

Any boost readings in Mb need to have 1000 knocked off to give you the real numbers. 2500 is 1.5BAR.

A bad temp sender wouldn't kill the thing. You can see what the ECU is seeing with the VAG-COM lead, just cycle through the blocks until you find it. It should be the same as the dash gauge.

I think it's too early to go blaming the turbo just yet.



Gavin

 

[S3 Nattie]

Well I got a maximum of 169.19 g/s when measuring the Maf which is about right for a standard 210. I only got the free shareware version of VAGCOM, think its the 409.1 version so not sure if I can measure boost. I first noticed it was a bit sluggish when I put normal asda petrol in. It is alway run on super or vpower but was really late for an exam and had no choice. It have filled up good few times since then so the fuel aint in the system anymore. The temperature on VAGCOM is slighty lower than the gauge ie 80 degree when the gauge says 90 although it does rise to 90 degree and stays there . Had a looked at the intake temp sensor earlier and it looked ****** so will replace that