Guide to removing / bypassing the N249 valve.

[Dalo Harkin]

I'm looking into this, mainly to reduce all the standard pipes that are known to leak boost, here is the dilemma, I have an ARZ engine and previous posts here dont think it has the N249, BUT I definatley have the reservoir on the top of coil pack 4, other than ripping the lot off and seeing if there is an actual N249 am I right in saying it must have one because of the reservoir?

[Granta Gti]

ARZs do have them mate, it says earlier in the thread they don't but they do! Done it to mine and it's an ARZ

[GTIcheeseman]

can this bedone to the agu 1.8t ? also what does this achieve?

[barry-gti]

AGU's dont have an N249.

[wasps1990]

I removed mine last week and will be putting it back on this week.

From my experience i Would not reccomend it to anyone. Car seems more jolty when accelerating, failed emmissions test! And the car still ticks over higher on a cold start so not really sure what it does lol. A lot of unburnt fuel was coming through on the emmisions test so i have a feeling this pump is always doing something. And also even if u put a resistor in the pump harness you still get a sai incorect flow fault code and engine management light.

So for anybody thinking of doing it i wouldnt bother!

are u talking about that mod or this one coz im thinking about doing this mod (n249 valve) but wont bother if it f**ks up emmissions n so on thanks alex

[Nino]

Just to clear this up, by doing this mod will it cause ssue with emissions? and can it be done to an AUM?

[Mr_Orange]

Just to clear this up, by doing this mod will it cause ssue with emissions? and can it be done to an AUM?

I did this to our AUM a couple of years ago.  Has passed two MOTs since then.  No worries   

[Nino]

Thankyou, i'll look into it then

[Dalo Harkin]

I removed mine last week and will be putting it back on this week.

From my experience i Would not reccomend it to anyone. Car seems more jolty when accelerating, failed emmissions test! And the car still ticks over higher on a cold start so not really sure what it does lol. A lot of unburnt fuel was coming through on the emmisions test so i have a feeling this pump is always doing something. And also even if u put a resistor in the pump harness you still get a sai incorect flow fault code and engine management light.

So for anybody thinking of doing it i wouldnt bother!

are u talking about that mod or this one coz im thinking about doing this mod (n249 valve) but wont bother if it f**ks up emmissions n so on thanks alex

Dont know what you actually did, but you cant have done something right

[tomparkes]

Bringing this back from the dead - I know, I know...

Just wanted to clarify (as some of the later posts are querying), bypassing the N249 won't affect emissions. BaV was talking about removing the secondary air pump, which is used to bring the catalytic converter up to temperature when cold starting. Removing this pump won't do much for performance (probably nothing actually) but will tidy up the engine bay at the same time as affecting emissions. If you remove it, make sure you put it back on before getting your car MOT'd

On a side note - I'm thinking of bypassing the N249 on my AUM to see what all the fuss is about - I assume this kind of "modification" needs to be declared to the insurance company? Before anyone starts having a go, I'm not the sort of person that wants to hide anything from them in order to save myself a few quid, I am genuinely unsure as to whether this would need to be declared. After all, it's bypassing something that already exists, not adding something fancy/expensive. Cheers.