Is this normal?

johnyfartbox

johnyfartbox

A2OC Donor
United-Kingdom
Should that flap be in that position when the car is not running, ignition off key out?
A2 TDI 75

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Cheers Sarge, I thought it should be, it would be open like that if the car was running full throttle maybe?
I actually started the car and checked it again while the engine was on tick over and it was in the same position.
Any idea why this is so?
 
I thought the butterfly valve only has 2 positions fully closed and fully open. With the engine running it is fully open. When you turn the ignition off the valve moves fully closed and then opens fully again once the engine has stopped - anti shudder valve. If you examine it not running I would expect to see it fully open, and if you were to inspect it with the engine running then turned off it should fully close and reopen.
 
Ahhhh, you have just explained to me the sound I heard when I shut off the engine earlier, I must have heard it closing, then opening up again.
Cheers audifan.........:)
 
its is electrically operated on the BHC/ATL engines, the flap is moving all the time the engine is throttling as it is used to encourage the EGR gases to enter the inlet manifold

Its normal for it to be fully open when ignition is off, it is closed for a few seconds to starve the engine of air when you turn off, but then opens fully ready for the restart

if you are on over run it will be nearly closed, wide open throttle fully open, accelarating fully open, but any time the EGR is opening it will be between 1/3 and 9/10 closed

Paul
 
audifan said:
I thought the butterfly valve only has 2 positions fully closed and fully open. With the engine running it is fully open. When you turn the ignition off the valve moves fully closed and then opens fully again once the engine has stopped - anti shudder valve. If you examine it not running I would expect to see it fully open, and if you were to inspect it with the engine running then turned off it should fully close and reopen.
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The vacuum-operated ASV on the AMF engine works as you describe. However, the electronic one fitted to the BHC/ATL engines does use intermediate positions to encourage exhaust gases to be drawn into the engine from the EGR valve. This was one of the minor changes that resulted in Euro4 certification for the BHC/ATL engine (AMF is only Euro3).

Cheers,

Tom
 
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