info needed on over-run cutoff valve

[Deefadog]

on my MK 16V!

What does it do? what is it connected to? what other (if any) valves switchs does it control?

if the elctrial connection is disconected would I lose power at all?

any info would be great


Thanks

[Deefadog]

sorry to seem impatient.

Anyone got any info or can point me in the right direction?

Thanks

[Gambit]

no you wouldnt lose power.

basically all it does is keep the rev's that little bit higher for a fraction of a second when you come up of the gas saying for changin gear. it helps improve fuel economy by about 1mpg but more importantly makes gear changin that little bit smoother.

the wee duffer (looks like a silver disc) on the back left hand corner of the airbox, sense's a vacuum when you come of the throttle it then opens the air tract runnin from the base of the airbox into the inlet tube and basically bypassing the airflow meter for that split second - if that makes any sense

[Deefadog]

Thanks, this was the cause of all the other problems I had, kangaroing and a bad flat spot between idle and 2000 rpm. I have only disconected the electrical connecton at the moment, so does this little valve sound like it could do all that or is there another process involved that would cause the problems?

Is there a vag part number on the valve at all? as today i phoned my VAG dealers and they said "er we can't seem top find it on the computer, do you have a part number?"  -  Stupid gits

[Gambit]

yes it has been known to cause problems - i wouldnt worry about it. it'll cost you an arm n a leg to replace

u'll probably find its not the we vacuum sensor but the actual air bypass valve connecting into the airbox as these are usually saturated in mucky oil that comes up the breather

[Deefadog]

Aha, i see, is that part the the electrical connection connects into, it's about 4" high and has stumpy pipes coming from it if i remember?

Might be worth taking it apart and giving it a good clean, it's the part of the pipe system i have not cleaned, typical

[Gambit]

it connects into the back of the airbox and the underside of the air intake pipe.

the pipes are about 1/2 inch in diameter, there is no electrical wires going into it. it only has a vacuum pipe running to that we duffer on the airbox.

its usually boggin with oil so be prepared for mucky hands

[Deefadog]

right I see, I am confused now as i disconnected the electrical connection just up from that, it's two wires in black plastic housing with metal spring clip and plugs up into something straight upwards (which I thought was the over run cut-off valve), what does these wires control?

[Gambit]

i dunno you've confused me also! i'll need to go look round an engine bay

[Deefadog]

Thanks mate, I can't take pics at the mo, I'll try tonight and show exactly where it is.

take care