N249 Removal / Bypass

**noone** · 09-09-2009, 05:00 PM

Well, this is an interesting topic...

The removal of the N249 seems popular on some 1.8's, is this relevant to the Polo GTI still?

Anyone have an opinion? Plenty of ideas on Vortex...

**philthy** · 09-09-2009, 06:18 PM

May I ask what is the N249?

**noone** · 09-09-2009, 06:31 PM

Have a look on Vortex.

It regulates the vacuum for the N75.

If your boost seems to fluctuate (I could hear it), its normally the N249 Valve that is affecting the N75.

I've already changed the N75 to N75J and am happy, but am interested in the possible benefit of having the N75 do the work directly.

The N249 is designed as a safety feature, so definitely not recommended to anyone who is worried about any potential damage to their engine as a result.

**h100vw** · 09-09-2009, 06:38 PM

I'd be fitting a boost gauge or data logging to confirm boost fluctuations.

On the N249, I am always wary of removing anything that VW no doubt deem essential. Doesn't seem sensible to me.

Gavin

**Plautos** · 10-09-2009, 12:39 AM

The N249 open the BOV when the boost is too hi.

It is a vacuum box over the engine controlled by a solenoid connected to the BOV.

**Kai** · 10-09-2009, 07:09 AM

Mine is removed. (not physically but its not hooked up)

**noone** · 10-09-2009, 09:28 AM

Its an interesting solution for those having issues with the turbo fluctuating when chipped.

I've had success with the N75J (no limp mode, boosts a little harder i feel) this mod is not required.

For those who are hesitant of changing the N75, this is an alternative if the boost does not feel consistent.

**mikepologti** · 13-09-2009, 04:03 AM

hmm i think i might get look into getting a boost gauge myself , not sure if its me or not but the boost doesnt seem very conisistant. ive checked the turbo plumbing again and seems tight. has anyone here had issues with n75j ? and can it course serious damage if replaced from stock n75?

**noone** · 13-09-2009, 09:54 AM

I do find it interesting that some people prefer the stock N75, some aftermarket. Some get limp mode, some get improved boost or more consistant boost.

TBH, I think that bypassing the N249 is quick and pretty easy. I think that if its the N249 that is moderating the boost (well, dumping some) then its getting in the way of the new chip functionlity.

You can bypass the N249 in 5 minutes, have a test drive and put it back. Here is a link to a basic 'how to'

I still found it a but confusing, if you want I can explain or take a couple of photos to demonstrate.