my zed wont tick over properly its fine when first started from cold but as soon as i rev it and it trys to come back down to idle speed it starts hunting(revs drop to nearly 0 then up to 1500) can any one help? if i remove the rubber hose that comes from the passenger side hard pipe on top of turbo to a contoll valve then its fine i`ve changed the part on the back of the engine that the pipe goes to and its still the same.the cars got hks blow off valves full exhaust with divorced pipes and front mount intercooler

Could be a number of things, cleaning a few terminals is the first to try.TPS terminals, MAF terminals and the yellow water temp sensor terminals are all common suspects and the cheapest solution to start with too ;)

...Oh and the IAAV ones too on the n/s rear of the engine!!

 

Hope this sorts it mate.