406oc.co.uk

well i bought a 406 sri which i liked cos its a turbo! But i fited a after market dump valve to the engine which i fought should be better for it and make a nice noise! But thats the problem! Theres no noise? But the car is picking up speed o.k? I need help bad! Cos its doing my head in!

I recently fitted a brand new dump valve to a a4 tdi same prob no noise, checked that it was fitted right and it was, turned out the dump valve piston was stuck couple of squirts of wd40 later it worked perfect. worth checking just incase.

Hello and Welcome mate

Have a look at this it might help, oh by the way the search box is the best way forward on these things



DiscoPol

Its a sign, take it off and throw it in the bin.

what does a dump valve do apart from that noise which someone described as a pigeon being stuck up the exhaust sighing when the clutch is pressed, i hear them alot on boras and it does my head in, perhaps for a novel feature but i couldnt live with one every day.

Theoretically, it's used to ditch accumulated pressure once your foot comes off the gas thus preventing your turbo surging as supply massively outstrips demand and therefore prolonging the life of the blower. Realistically, it's used to make your car go 'WOOOOSH' when you change gear, thus making you look cool and rich and well-endowed. Er, no offence to OP

i'm no expert but there are different types of dump valves. both do the same thing, but they do it differently. one is an externally dumping valve which dumps it to atmosphere (the psssstttt type) and the other dumps it internally and i think this is dumped into the inlet somewhere.

The funny thing is a recirculating dump valve is considered best because it uses the 'blast' of air and pushes it towards the turbine on the inlet (compressor) side of the turbo and gives you a free 'spool up' reducing turbo lag........tell that to the 'woosh' lovers though and you'd be thrown out of the Maccy Dee's car park

Welly wrote:The funny thing is a recirculating dump valve is considered best because it uses the 'blast' of air and pushes it towards the turbine on the inlet (compressor) side of the turbo and gives you a free 'spool up' reducing turbo lag........tell that to the 'woosh' lovers though and you'd be thrown out of the Maccy Dee's car park

had that exact argument with a mate of mine, and after ages of saying i was talking crap, he gave one a shot and reckons the difference is actually very noticeable, plus you can still her much nicer sounding and less in your face chatter from it.

I just plain love the basic turbo whine, can't hear it so well in the Omega but in the 406 once it went north of 2k there was this wonderful sound like a small jet engine winding up

2.2's are fairly noisy when the engines cold & the air goes through the water/air heat exchanger, (which is smaller diameter), instead of the intercooler.
At first, I kept scanning the mirrors to see where the siren was coming from.