The small breaded one goes to inlet yes? If so that's correct mate should be 2 big rubber ones and that
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The correct way to do an N249 bypass the full guide
- Thread starter mc funbot
- Start date
No, it comes off the unit where the n249 is and runs along where the two rubber ones go that also come from the n249. Do you have to remove all the n249 and pipe work or can you just run a pipe from the dump valve to the inlet manifold the 't' it off to the fuel pressure regulator?
You can but that's not doing anything different to as it is standard.it really is simple. Everything gets removed pal then just run your new vac line.
These are the 3 pipes coming off my n249 valve. All 3 of yours are rubber so do I just cut and block the braided one?
this is where it runs to
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Yes mate that looks about right. It's the same as the other engines.. Block the braided one and then enjoy 
Sorry for the stupid questions... So basically remove pipe from top of dump valve and metal pipe. Remove pipe from black box and metal pipe. Remove 2 rubber pipes from n249 and metal pipes and remove the braided hose and block? Then do you just remove all the hoses from the underside of the bracket where the n249 is and then plug connectors in with no pipe work. Correct?
Also I have two vac nipples coming off the inlet manifold. One goes to the fuel pressure regulator and the other goes to the n249. Guessing you can just leave the one that goes to the fpr and us the one that used to go to the n249 and run the new vac line from the dump valve to that nipple?
My EML came on today. Done a code read and cam up with secondary air injection incorrect flow. Anyone had this after removing the n249 valve?
I did this guide for removing the n249 and all the pipe work. Few days later EML on with sai incorrect flow. So am I right in thinking I need to remove the air pump?
Yes you can so. Only know this happen a few times I need to go a guide for removing it. Quick way round it go under the front and just unplug it can out a resister in it from eBay there £5 or just see how it goes. The plug in my Ibiza don't have one in and it's ever brought up a code. All cars seem to act a bit different.
can out a resister in it from eBay there £5 or just see how it goes. The plug in my Ibiza don't have one in and it's ever brought up a code. All cars seem to act a bit different.
Mc Funbot fancy helping me do a bypass on my LC? Im from Northants so could come to you at a convenient time...There'll be a Big Mac and beer in it for you 
Hello mate. Well funny you should say that because yes I can inbox me if you like and we can sort an evening to do the bypass
inbox me if you like and we can sort an evening to do the bypass
Sound nice one.Cant pm you yet tho...still a noob at mo!Been on this site a few years now but only just started posting.Ill give you a shout next time ive got some leave.
Pamdam
Guest
hello,
just seen this thread as i have been looking into the n249 delete, i bought my car with this already done but i have had trouble with it dumping boost still. I have just noticed int he picture the previous owner who did mine has done everything but left the dv connected to the hose that runs to the n249 and not to the nipple on inlet and not removed and blocked the other pipes so kind of half a job. would this cause the problem I'm having specifics are below;
in 1st,2nd,3rd i get peakboost at 19psi and it falls off to 10psi and holds
in 3rd, 4th, 5th i get 18-20 psi and it holds
in 6th i get 21 spike then drops and rises again between 16 - 21 psi with my foot flat
i have deleted pcv, 4 bar fuel reg, new waste gate actuator, checked for leaks, replaced n75 with a tt 225 one, the exaust is a 3" with decat straight through, ram air induction, front mount, the usual little bits of maintenance have been done.
any help would be great because if it isnt this im stumped.
cheers
just seen this thread as i have been looking into the n249 delete, i bought my car with this already done but i have had trouble with it dumping boost still. I have just noticed int he picture the previous owner who did mine has done everything but left the dv connected to the hose that runs to the n249 and not to the nipple on inlet and not removed and blocked the other pipes so kind of half a job. would this cause the problem I'm having specifics are below;
in 1st,2nd,3rd i get peakboost at 19psi and it falls off to 10psi and holds
in 3rd, 4th, 5th i get 18-20 psi and it holds
in 6th i get 21 spike then drops and rises again between 16 - 21 psi with my foot flat
i have deleted pcv, 4 bar fuel reg, new waste gate actuator, checked for leaks, replaced n75 with a tt 225 one, the exaust is a 3" with decat straight through, ram air induction, front mount, the usual little bits of maintenance have been done.
any help would be great because if it isnt this im stumped.
cheers
Well best things to do follow the guide an then see how it goes.i take it the car is mapped. If so did they want the 4bar fpr in to do this? You have a put a tt225 n75 In that could be a problem as it maybe requesting more than you want or can give from the duty cycle of the n75. Do the bypass an see.what dv have you got. Post some pics of your bay so I can see. Hope we can help
I've just finished following this guide today on my AUQ engined LC - had done the bypass a week ago and no ill effects. It's made the bay so much less hassle to navigate. Especially the front, under the manifold.
I had been getting fluctuating boost on partial throttle, it would build to around 0.4-0.5bar then dump and start building again which was really uncomfortable. Seems to hold better at higher revs too.
I'm still using the stock DV and it's a completely different sound to what it used to be, more of a "tis" than the old "psssh".
Highly recommend this and the guide was brilliant. Not sure where people struggle, I expect it's having the stones to start ripping out pipe from an engine bay that was designed by people with more letters after their name that we have!
I had been getting fluctuating boost on partial throttle, it would build to around 0.4-0.5bar then dump and start building again which was really uncomfortable. Seems to hold better at higher revs too.
I'm still using the stock DV and it's a completely different sound to what it used to be, more of a "tis" than the old "psssh".
Highly recommend this and the guide was brilliant. Not sure where people struggle, I expect it's having the stones to start ripping out pipe from an engine bay that was designed by people with more letters after their name that we have!
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