hey all

ive a bosst stuttering problem and was advised to swap out the n75 valve. can someone give me a pointer to where its located and if theres a guide on how to remove and replace

apologies if im being lazy but i ive read threw a load of posts on this but havent found the right one yet. seems to be a very common problem with an error code along the lines of 17705 or something like that

also came across a guie on cleaning the throttle body...was going to do this first...could it help or am i barking up the wrong oak tree

thanks

Edited 14 April, 201016 yr by huwants2no

just read in useful paRT NUMBERS the N75 valve is the dump valve so ignore the above

why not just call it DV instead of N75

nevermind

The N75 is NOT the DV. It's related to boost but not the same thing.

Check out the engine diagram here:

http://briskoda.net/forums/topic/154622-18t-auq-engine-diagram/page__p__1929511__hl__diagram__fromsearch__1entry1929511

Also have a read here:

http://briskoda.net/forums/topic/156772-n75-valve-question/

The N75 is located on the large thick intake pipe between your air filter box and the turbo. It's a little box shaped thing (looks a bit like a relay) with small vacuum pipes going into each side. Whereas the DV just releases excess boost when you close the throttle, the N75 has control over how much or how little the wastegate opens depending on the pressure in the inlet and what the ECU is telling it to do.

Yes the 17705 error code usually indicates a boost leak but it is cheapest to look at other things first like checking all the vacuum pipes and boost hoses, hose clips etc., cleaning the throttle body, then if that doesn't work start moving on to checking and replacing valves like the N75, divertor valve etc.

Edited 14 April, 201016 yr by chicken_eyebrow

The N75 is located on the large thick intake pipe between your air filter box and the turbo. It's a little box shaped thing (looks a bit like a relay) with small vacuum pipes going into each side. Whereas the DV just releases excess boost when you close the throttle, the N75 has control over how much or how little the wastegate opens depending on the pressure in the inlet and what the ECU is telling it to do.

Yes the 17705 error code usually indicates a boost leak but it is cheapest to look at other things first like checking all the vacuum pipes and boost hoses, hose clips etc., cleaning the throttle body, then if that doesn't work start moving on to checking and replacing valves like the N75, divertor valve etc.

sounds like a good place to start. have had a couple of hoses give up already,the Y shaped one to the laft of air filter and a breather hose under the manifold. didhave a look round to see if anymore where leaking but icould easily of missed some of the more tricky ones to get at. also came across your guide for cleaning throttle body last night reading up on others posts re similar problem so will definately do thatbefore changing any valves.

if I was going to replace the N75 do I have to get new one or is this something that can be got elsewhere. maybe that kind of defeats the purpose

anyway thanks for the help as usual

The N75s come up on ebay quite often for about £20 cheaper than they would be if you bought them brand new from the dealers. If you really want to save ££s then see if there is anyone with a similar car, anything with a 1.8T engine (try Vagdrivers.net if you're in Ireland) that will be happy to swap over N75s to see if it fixes it the problem then it's worth buying one

Edited 14 April, 201016 yr by chicken_eyebrow