1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

S3 post remap N249 bypass . ! . ? . ! and fuel pressure reg question

VAG-Slag Jul 15, 2011

  1. VAG-Slag

    VAG-Slag Well-Known Member

    so, just had my S3 remapped (AMK) and the diagnostics threw up a mechanical fault with the N249 but we went ahead with the map anyway.

    The geeza who remapped it swears by the N249 and says I should replace it. I mentioned that loads of people bypass it and he claims there's very good reason Audi put it there in the first place, to help control boost, and that I should keep it.

    I've seen a few threads and everyone seems to think it's deffo worth bypassing but I just wanna be clear. No one seems to have a proper reason to keep it or indeed to bypass it.

    Also, the guy rekons that the standard 3bar fuel pressure regulator will provide enough fuel for up to about 290 break and that other tuners upgrade em to 4bar anyway just to make a bit extra on the side.

    What do you guys make of all this? What should I do!?

    Also, even if I do bypass the 249 do I still need to get the fault cleared on the diagnostics?

    Thanks guys! All opinions appreciated!
  2. superkarl

    superkarl MAN OF STEEL

    This 'geezer' clearly doesnt know what the n249 does. It does not control boost in anyway, it opens the dump valve when the esp comes into action, that is all. I'd bypass it, but, you are still supposed to have it electronically connected, so if it is bust, you will still need a new one. The main purpose of bypassing it and getting rid of associated **** is that it minimises boost and vac leak problems, but also improves dump valve response.
    As for the fpr, youl be fine with a standard 3 bar, for some reason people think theyrr needed and an upgrade, yet people running big turbos etc still run the standard one, all a 4bar will do is kill your fuel pump quicker.
  3. VAG-Slag

    VAG-Slag Well-Known Member

    Cheers buddy, that pretty much tells me exactly what I wanna here.... apart from the fact I have to spend money on a new N249, do'h! I suppose that way it's a win win tho; i'll replace the valve, see how it goes, then maybe think about doin a bypass on it.

    In theory, could the faulty valve be dumping boost back into the inlet then?

    As for the FPR, that's pretty much exactly what he said :)

    I would usually go to AMD for this sort of thing but thought I'd give these guys ago as they're closer and had an offer on @ 230 quid. Know one really seemed to have anything bad to say about em apart from some guy who swears they scratched his car. So far so good, thanks storm developments for a cost effective map. Will let you guys know if I have any dramas!

Share This Page