Still not running properly

[petewon]

Well its still not running as it should. Ive changed coilpaks, plugs, MAF, air filter. Starting to look towards a boost leak or possibly a faulty diverter valve.

Can anyone tell me where the diverter valve is in a B6 A4 1.8T engine and if theres any way to determine if its shot by visual inspection?

Also something Ive noticed is when I used to switch the ignition off I would get a winding down sound which I allways asumed was the turbo spinning down. It doesnt seem to do that anymore although I can hear/feel the turbo whistle and kick in while driving still so I asume its working ok. On a side note to that, I was in my mates non turbo clio last week and when he switched the engine off it made the same noise Im refering to above, so perhaps its not the turbo Ive been hearing all along.

Any ideas?

Cheers

 

[enda1]

Pete
Can you tell me the car year and engine code and i'll try to get you a schematic of the turbo layout

 

[petewon]

Thanks Enda, that would be realy handy. Im gonna be looking for a boost leak but realy not sure which hoses to check. Its like a pit of snakes.

Anyways its 2001 first of the B6 and the engine code is AVJ.

Cheers again.

Pete.

 

[enda1]

petewon.

Don't know if this is much help beyond the last layout I sent but I'll send it anyway.

 

[petewon]

Eye cheers Enda. Do you know if the DV also know as the Air recirculation valve?

Thanks

 

[enda1]

Petewon.

i'm no expert here but i think the Air recirculation valve is what is known as a dump valve. You could ask a few of the guys who have fitted DV's where they go/what they replace and if they have any photos.
The hand held vacuum pump that audi talk about can be bought for aroung £20-30 under the brand name mighty-vac. i think halfords might sell them, it also works as a brake bleed kit and is very handy

 

[petewon]

Cheers enda, yeah I think some people call the diverter valve a dump valve. They have it listed on vagparts as a dump valve. Ill try and find someone whos fitted on if they know where it is. I had a quick look and cant find any vac leaks but Its realy cramped in my engine bay and difficult to see the hose going into the turbo.

Thanks.

 

[macca]

dump valve is black and is on drivers side front of engine bay, down above air con compressor if you have one fitted, you'll see two larger pipes and one small pipe connected to it, the small pipe will go round front of engine and upto the inlet manifold/plenum chamber. if faulty most people replace with a forge metal one which i think now costs upto £100, but maybe over kill if you're not tuning the car. i have a standard one somewhere if i can find it, if you want it pm me and i'll post it to you, it's of a 1998 b5 a4 1.8 turbo, but is probably the same.

 

[petewon]

Cheers Macca, I think I know the part your talking about, just behind the radiaor. Do you know if its also known as the diverter valve?

That would be excelent if you could dig the old one out mate.

Cheers.

 

[s4mark]

i have been told the diverter valve and dump valve are the same thing. I changed mine on my previous Audi (2002 A4 1.8T) after having the REVO Tecnik tuning programme carried out. Replaced it with a Forge recirculating Dump Valve (£105), noticed an improvement in terms of reduced turbo lag. The forge recirculating DV is very quiet in operation which suited me down to the ground.

Also took about 20 mins to fit, accesed by removing undertray under front bumper. You need to prise off the metal hose clips. I replaced mine with Jubilee clips as they do exactly the same job.

In response to the whirring / spinning down noise you mentioned when turning the car off, is the air con / heater unit i think but cannot be 100%

Hope this is of some help

 

[petewon]

Cheers Mark thats a big help. I was looking how to get into the DV and read somewhere about going in through the light cluster??? I think the undertray idea is gonna be a lot easier.

Also the whirring sound is the air con, I just havnt been using it much recently and was thinking it may have something to do with the turbo.

Cheers for the help.

Anyone got a cheap 710N DV for sale

Cheers