Octavia vRS Turbo/Dump Valve Problems

[dswhite]

Hi All,

I've been watching this forum for a while now, and it's helped me out on a number of occasions, (like when a coil pack went) but this is my first post.

I've have a 51 plate Octavia RS for about a year now. It's done 90k, of which I'm responsible for 17k worth (mostly on the A1M), and in that time it's been great and I'm really pleased with it. However I've noticed recently a strange problem that I'm hoping you guys can help with:

If you accelerate hard from low revs, (i.e. below the point at which the Turbo comes in - 2k RPM ish) the revs rise and at about 2500 rpm the engine blips a few times before you get the full force of the turbo. It feels much like when you get engine braking on decelleration, and I'm almost certain it's not a missfire. It doesn't happen all the time, and once you're in the turbo zone it's fine no matter how long you drive or how many gear changes you do. I've also noticed that if you subsequently slow down and leave the revs at about 2000, it tends to blip again, almost like the engine is momentarily braking itself. It's perfectly fine at idle.

I'm wondering if the dump value isn't opening/closing properly and creating back pressure from the Turbo?

If anyone has any ideas/theories, then I'd be most grateful.

Dave

[Joel_vRS]

Im not very techcie when it comes to engines learing fast tho...it may be a DV probelm are you still on your orginal DV?? 90k it alot for this part there only

[SkodiRS]

Im not very techcie when it comes to engines learing fast tho...it may be a DV probelm are you still on your orginal DV?? 90k it alot for this part there only

[KLB]

Are the symptoms like the ones described in this thread? Diagnosed as a faulty N75 valve in the end.

[dswhite]

Thanks for the repiles.

As far as I know it's the original DV, although it's hard to know what the previous owner had to have done to it. For the sake of

[Joel_vRS]

the DV is located under your platic cover top right hand corner really easy to swap out for another

is the traction control only working when the light indidcates then? i was under impression it was regualting your every move light or no light...the light i thought was ti indicate complete loss of traction

Joel

[DGW]

The pic below shows the location of key components in the engine bay:

[KLB]

Thanks for the repiles.

As far as I know it's the original DV, although it's hard to know what the previous owner had to have done to it. For the sake of

[elegance1.8T]

Does anyone (DGW!!!) Have the price for a N75 as mine appears to be doing the exact same as Declac's was before, i've lived with it for nearly a year now. Are they easy to fit?

(Sorry for hijacking thread)

[elegance1.8T]

Sorry just looked on vagparts and its

[fastVeRSion]

Mines been back and forth to the dealer for the same thing - they've been hopeless, to them no error code = no problem...

Do vagparts sell oem stuff? At 35 quid, I'm gonna buy one anyway if its a genuine part. Maybe it'll fix the problem, maybe not but it's 1 less thing that could be the cause.

EDIT: 'For all your VW, and Audi Genuine Parts...' kinda gives it a away...

[SkodiRS]

IIRC for

[DGW]

The part number and ETKA price of the N75 are in the thread below:

http://www.briskoda.net/forums/t4685-useful-part-numbers.html

A lot of the prices in that thread need updating, but those for the DV and N75 are recent.

[fastVeRSion]

Vagparts only lists the part number 034906283J for Golf / Seat as opposed to the other thread - 058 906 283 F.

I'll probably go for a standard one as i'm trying to fix a problem and don't want to introduce anymore variables.

[DGW]

I'll probably go for a standard one as i'm trying to fix a problem and don't want to introduce anymore variables.

[elegance1.8T]

Had another look on vagparts and they have that model in 058906283F, it says for an S3 hence my other searches didn't show anything up. Price is

[SkodiRS]

I think you are wise to stick with the F version. IIRC some members have tried the J but reverted back to the F.

(Sits back and waits to be contradicted...:( )

I think the J version is fine....it just didn't sort the issue I hoped it would. :(

Believe the N75J was originally used for the Audi S2.

[elegance1.8T]

Well i've just ordered the 'F' from vagparts so lets wait and see.......

[dswhite]

I've just driven my RS home and if it's going to play up it does seem to be when the revs are between 2-3k rpm. I'm placing my bets on the N75 valve, so I'm about to order one and see what happens.

Thanks for all your help guys!

Dave

[GAFF]

I had hesitation between 2500 & 3000 rpm when cold, I don't know if it may be the same issue as you but it turned out to be my DV. Do a search for 17705 (there was a number of posts on it)

[fastVeRSion]

Had another look on vagparts and they have that model in 058906283F, it says for an S3 hence my other searches didn't show anything up. Price is

[Delcac]

I think the J version is fine....it just didn't sort the issue I hoped it would. :(

Believe the N75J was originally used for the Audi S2.

Adrian,

So do you know what the actual part numbers is for the type J, is it the same as the F but with a J at the end if you see what I mean.

Just to throw a spanner into the works I finally opted for the type C which I am told is the same as the F but I found it smoother.

[SkodiRS]

Adrian' date='

So do you know what the actual part numbers is for the type J, is it the same as the F but with a J at the end if you see what I mean.

Just to throw a spanner into the works I finally opted for the type C which I am told is the same as the F but I found it smoother.[/quote']

Des,

I got this one:

N75J

Like I said I was chasing an issue and thought it might cure it......read about it on CupraNet adn why peope were using them.

Still got the same issue....maybe I should try a N75C now?