Need a bit of help !! Replaced standard dv valves one was split with 14 psi ones Car has dms remap and was pulling 1.0 bar - 1.2. Now only spiking at .8 whirring noise from right hand side side and drives like it has a broken actuator rod ( it hasn't ) Maf changed n75 changed plugs changed rods free. Any pointers greatfully received .

Cheers Fraser

 

What do you mean by "one was split with 14 psi ones"? Sorry, I can't understand that.

Are you sure its not some other hose, like an intercooler hose? Have you adjusted your actuator pre-load lately? The preload being too low can make an air rushing sound during normal driving.

 

Sorry. One of the standard Bosch diverter valves was split . These were replaced with the upgraded 06A145710N part number. These are a stronger valve and require more vacum to open. I have tested before fitting. I know there must be a leak somewhere as it now appears the vac pressure is not strong enough to open them . The car now runs as if only one turbo is spooling. I was looking for pointers to which hose / hoses may have failed and if this would cause these symptoms . The car ran quicker / pulled more bar with the old perished dv fitted !!
Thanks

Fraser

 

Check your vacuum hoses for splits and make sure they are seated properly some people plastic tie to secure. Do a boost leak test.

 

..and 710n's shouldn't function differently.. all it takes is an i/c c clip to pop a hose so agree with testing. but always start where you stopped. switching out dv's is revisit #1.

 

The engine vacuum opens them when you come off boost. If you had a bad vacuum leak then they would open slower. It sounds more like a boost leak. Boost is what holds them shut.

It seems unlikely that they could cause something that big. Did you take the hole y-pipe out to do the change? Maybe you didn't reconnect the hose that goes to the turbo intake plenum?