I just fitted a forge split-r dumpvalve to my 1.8T (150bhp) A3. Now when i ease off the accelerator i hear the valve dump but when i ease back onto the accelerator its quite jerky. Im running the valve part recirc part atmospheric. Anyone got any ideas? have i got it set too stiff etc?

 

You need to play with the spring stiffness setting. This adjust it to how much vacuum is needed to open it and how quickly it shuts.

 

Thanks Mike, i have had a bit of a play now and it seems better but im not convinced its how it should be

 

Have you tried making it 100% recirc to see if the issue goes away?

 

No i havent to be honest, ive slackend the spring off a bit more and it seems better no but i i havent given it a good run yet so if it is still playing up il try that next