been looking at getting a new N75 valve in hoping to fix this 17705 code ( pressure drop ) . ive been looking and theres afew you can get , like n75 k , n75 j and so on .

ive got a mk1 VRS on a 2001 plate . how do you know which one to get or are they all the same ?

It came with an F as standard, which has since been superceded by the E. Some people use J and H valves to help with tuning (hold boost longer etc), but these seem to be pretty hit and miss. HTH.

:iagree: TBH without trying them all you will never know what runs best. As for it being a cure to the 17705 I'm not convinced.

Ian

N75J valves only seem to work on mapped engines, and even then some maps like them and others don't.

I had one on my old mapped Octy vRS, and that held boost far longer than the standard one.

Are you sure its the N75, as it could be other things, and there are threads on here covering most of the attempted solutions?

Stick with the F or E as it is now. You may encounter over boost issues if you go with the other valves also the car was supposed to run with the F/E valve from the factory and the map is setup to run these.

As the guys have already said, stick with the standard one, the J is more trouble than it's worth by the sounds of things.

058-906-283-F is the part number for the N75 "F"

TBH it sounds as though you may have a boost hose issue, especially if it's dropping alot.

Steve;)

not sure what it is , ive had the pipes all off and checked and nothing wrong with it . cleaned the TB and revs are loads smoother but still got this code . change the DV and still there .

been told to change the seals on the turbo and intercooler but i want to change the N75 too just in case