Got problems with my dump valve. Its a Bailey Double Piston Dump Valve and works great when the turbo is fully spooled up. But when its not i.e. when i make short gear changes etc it tends to make a weird noise, almost like a "farting" noise. Anyone have any ideas?

Cheers

Chris

Check out "Honking DV" on this site http://dv.mistertam.com

(EDIT: Welcome to Briskoda :cheers: )

Wouldn't have thought honking was the problem as this only happens on OE DV's AIR.

It may need regreasing or the spring is too strong and won't open/shut making the waste gate chatter. It may also be fitted the wrong way round, not that anyone on here would be so silly.

Des

Is it a Bailey DV30?

It isn't a DV30 or diverter valve. I replaced the OE with a atomspheric valve.

I'm totally confused, Chris! Is it a Bailey double piston dump valve (first post) or an atmospheric valve (last post)? And what car are we talking about?

Chris,

If you have a stock VAG 1.8t engine, then a straight atmospheric dump valve probably isn't a good idea.

The problem is that the DV sits downstream of the Mass Airflow Sensor (MAS, or MAF) so when it opens it's dumping air which has already been metered by the MAF. This confuses the ECU and can lead to problems. The best solution - if you aren't satisfied with the OEM diverter valve - is to get an aftermarket diverter (Forge, Bailey, or similar). Some people have used "hybrid" (part recirculating, part atmospheric) DVs successfully, but I can't see the point - you risk knackering your engine just to get the "psssht" sound. Better to get a decent CAI (try a search for "CAI" on this site) kit to improve the sound of the standard DV.

(EDIT: Here's a block diagram of an engine which is very similar to the 1.8T http://klb.briskoda.net/pix/tech/pictures/blockdiagram.jpg+ )

Sorry :(

Its a double piston dump valve (thats what i was told due to the map sensor so needs to be double piston) and is atmospheric i.e. the air intake hole how has a bunge in it.

I this helps?

Cheers

Chris

The OEM DV is a diverter valve whihc vents into the airbox. I don't think you can use a BOV???

If you want more of the BOV sound you can either get an aftermarket DV and a CAI or, get a hybrid DV (ABD, XS etc). I don't think the ABD one works very wel on remapped cars but works fine on standard.

Farting noise? Sounds like the waste gate is fluttering where boost is being vented out the waste gate. Bad as this will knacker you turbo!!!

I think this is generally correct....one of the old Sages wil correct me I'm sure.

Chris,

Can you tell me who has supplied your DV and what was the reason for recommending a double piston DV.

Des

You can just tell when Des has gone into 'terrier' mode. :blowinup:

A friend of mine recommded a double piston valve because of the way the standard dump valves work and because of sumthing to do with the way it effects the MAP sensor. I also wanted a atmospheric DV because the noise they make will keep a smile on my face all day long!

Cheers

Chris

Chris,

Do you mean MAF sensor or..............I'm just loosing the will to live here. :(

Des

lol i'm just going by what i have been told! Mite be the MAF sensor as i may have misheard?

Chris' date='

.......I'm just loosing the will to live here. :(

Des[/quote']

Oh dear........sounds like Des is going cold turkey on parting with his RS.

zzzzzzzzzzzzzzzzzzzzzzzzzz!

Soz was only asking for help! Just thought it would be nice to hear sum peoples expericences with atmospheric dump valves. Gonna take it to a garage 2morrow and see wot they have to say.

Thanks anyway

Chris

CAI and inverted DV will give a great psttt sound on lift, nice fluttering and ssssssshhhhhh can be acheived. However inverted DV's are not to be recomennded as you loose boost apparantly ( only a iccle ) but hey im worth it for the sound. a dv006,7 or R, hyperboost ( I have ), AmD's Viper or others...a Dv is a DV, plenty of reviews on the web and here ( I hope soon ) or them all.

but it's a diverotr and not dump/bov style afaik and what they said. please keep us all informed...n75 flutters aswell I think, or somthing down there does on mine, near silent on stock airbox, add induction filter, very obvious...anybody?

I'm pretty sure my waste gate flutters sometimes.....I guess it another things they all do??

I think Chris has the wrong type of DV fitted....well it's not even a DV it's a BOV. 1.8T not designed for a BOV...I suggest he gets a proper DV.

I read a thread on SeatEnthusiats about Bailey (or was it Forge) atmo DV.....upshot was it didn't work properly.

Thanks for all the info, i'll keep you upto date with the outcome.

Cheers

Chris

Chris - i've been trying to run a partial-atmospheric DV on mine for some time and it just dont work - so if yours is fully atmospheric i'm amazed you got it working!

I got bored of trying and got a forge 006 instead

Got it all working spot on at last. Had to modify a pipe! I'll post pics when i find my camera :smile-l:

Same "fart" noise on mine when releasing throtle - (all standard 1.8T + upsolute chip) - still waiting for the pictures

Robert

To fit an atmospheric DV on a recirculating system is a bad idea!

may be ok a race engine as they respond a bit faster to dump

do one simple test on your car at idle and i recon you'll change it asap - really simple - put your hand over the 'to atmospheric' end of the DV - it will suck air! remember that this air is not filtered!

TAS (wigan based) do a piston OE Bosch DV replacement which is adjustable to get the seal right (this it the important bit with an uprated DV - i have one on my lancia but doubt it is of any real benifit unless you are running >1.5bar boost (WARNING set the spring too firm and you wont dump causing turbo/wastegate problems - that said Cossy Boys recon there is no need for a DV below 1.5bar and the original audi quattro didnt have one at all!)

The TAS piston type costs about