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The correct way to do an N249 bypass the full guide

Liam180cupra

Active Member
Jan 27, 2016
113
0
quick question guys.

Which pipes do I need to block?

Also I have seen people connecting the egr and manifold pipe connected to go to DV?

cheers in advance
 

Bristbro

Active Member
Apr 11, 2016
9
0
I got a fault code about boost pressure control valve 17608.

So i may try and do this By-pass on the weekend when i'm stripping the interior and re-sealing all the doors... ahh the joys :whistle:
 

Bigjohn84

Intagram / johnyoung84
May 5, 2015
2,330
1
Take DV pipe of and stick a bolt in the pipe you just took off, put a new pipe on the DV and take it down to ur FPR, take the FPR pipe of also, conect a t piece to the end of the pipe from the DV, Cut a piece of pipe and attach it to the t piece and conect to the FPR and the last piece of the t piece conect to the nipple under the manifold, done.
 
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Liam180cupra

Active Member
Jan 27, 2016
113
0
I cut all the pipes and removed them from n249 and n112 valves.

I then ran a new feed from the dv to the nipple under the manifold.

I then stuck a bolt into the n112 pipe that comes from the side of the block. think it attaches to the secondary air injection combi valve.

Just double checking this is right.
 

Liam180cupra

Active Member
Jan 27, 2016
113
0
Cheers mate.

Which pipe would i T the n112 pipe into? The dv?

Since doing it i have had the sai code on which doesn't really bother me but rather be eml light free
 

Bigjohn84

Intagram / johnyoung84
May 5, 2015
2,330
1
I wouldn't bother mate. Heard a few bad things happen. If your near Edinburgh I have vcds
 

Andrewwright

Turbo lover
Aug 16, 2016
1,562
219
Peterborough
Mc funbot what code reader should I buy for my mk1 cupra 180 2001 y reg I'm confused with what's what over on ebay. I'm from Peterborough and not sure if and were I could buy one of the shelf. Needs to be able to clear errors not just read them? Could you point me to the right device please.
Reason I ask is if I plug in maf the car idles really bad and try's to stall. Not drivable so replaced maf with new one and same thing. Unplugged runs ok i think. Not had a turbo car before.
Many thanks
Andrew.
 
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mty12345

Active Member
Jun 17, 2011
3,196
208
bristol
Mc funbot what code reader should I buy for my mk1 cupra 180 2001 y reg I'm confused with what's what over on ebay. I'm from Peterborough and not sure if and were I could buy one of the shelf. Needs to be able to clear errors not just read them? Could you point me to the right device please.
Reason I ask is if I plug in maf the car idles really bad and try's to stall. Not drivable so replaced maf with new one and same thing. Unplugged runs ok i think. Not had a turbo car before.
Many thanks
Andrew.
Hi andrew, first off i'm not sure there is even any point doing a N249 bypass tbh. What is it you are trying to achieve by removing it? we've had this debate time and again and apart from the space saving aspect then there's really no point IMO, however it's your car and it's up to you. ( I don't want to start yet another debate on it,lol) However here is my reason for NOT removing it http://forums.vwvortex.com/showthread.php?6881579-Why-you-should-keep-the-N249

The MAF thing comes up time and time again too, and is one of the most misunderstood things on modern cars. When you unplug the MAF, the car shuts off all fuel trims and runs in "open-loop" rather than "closed-loop" mode. It also defaults to it's back-up engine maps because it now has to guess how much air is entering the engine rather than being able to actually measure it.

Unplugging the MAF will often make the car run better, but this is simply because by unplugging it you've disabled most of the systems that control fuelling, not because the MAF is in any way faulty. Every time a MAF has actually failed, you should get the fault code for that. They are usually fairly reliable, as long as you don't use an air filter that needs oil on it, like some aftermarket filters use. Again IMO stick to a good panel filter in the original airbox instead. If the MAF ever does need replacing, then only a GENUINE BOSCH one from eurocarparts or similar will do. A cheap ebay job will not work.

Anyone who tells you to unplug the MAF to test if it is working/not working, simply doesn't understand how the system works! You'll just end up spending £80 on a part you don't need. The only proper way to test it, is to look at the live data reading from it.......For the 180bhp engine you should see between 2 and 4 G/S of airflow at idle (with a warm engine) if the MAF is ok.

Any OBD2 code reader will do, however if you plan on keeping the car for a while then get yourself VCDS http://www.gendan.co.uk/product_VCHU.html Yes it's pricey at almost £300 but will probably save you that amount plus a lot of headaches if keeping the car long term. With VCDS you can not only get far more fault codes than you can with a standard OBD2 reader, (OBD2 will only read engine, brakes, airbags etc, VCDS will do fault codes for every system in the car possible I.E locks, air con etc etc) but you can also do live readings and data logging with it as well.

If you have an android phone then "torque" from google play store (£1.49 i think) Plus a ELM327 adaptor (see link below) will allow you to read and reset a limited amount of engine related codes. http://www.ebay.co.uk/itm/New-ELM32...637863?hash=item23701a76a7:g:97EAAOSwU-pXuGYQ

Sorry for the long essay, but i hope that it may have cleared up a few questions for you.

Matty
 
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mc funbot

its a beast its got boost
Jan 29, 2010
1,473
4
sunny kettering
www.seatcupra.net
Code reader of eBay about £15
Smart phone obd plug in about £5-10

As for the bypass up to you buddy the thread was build to show it being done properly not T of the FPR and leave other bits connected with a half assed job.

I've had the n249 n112 etc bypassed know my ibiza running 350bhp for over 6 years and fauktless. And my mums Leon the same.its your car mate.if you need owt just drop me a message on here.
 

Andrewwright

Turbo lover
Aug 16, 2016
1,562
219
Peterborough
Fauktless lol sorry had to.
Well seems if these things are removed then they can't go wrong/need replacing and therefore save you cash in the long run so seems really good to do this and it cleans up the bay nicely too! I'm not gonna be running anywhere near you output so should be fine me thinks :)
What sort of cost/time is involved for you to do this mate? Also all the others that can be removed, I read a blanking plate is needed. Don't expect cheap mate.
Also when are you available to do it?
 

mc funbot

its a beast its got boost
Jan 29, 2010
1,473
4
sunny kettering
www.seatcupra.net
Morning. 4mm vac line 2meters to be safe it's hours work just a few beers tokens that's all buddy I can vag com aswell mate sure it's all as it should be the blanking plate is for the said to be removed little bit more work nothing to bad though gets rid of quite a bit.
 

Andrewwright

Turbo lover
Aug 16, 2016
1,562
219
Peterborough
As for me doing it most evenings buddy.
Vag-com! Yes in need of that me thinks. Have engine light on since "first heavy left foot action" she went like sh#t of a shovel then limp mode,thought I'd popped the turbo. Thats when I've unplugged the maf as it wont run with it plugged in. An abs light came on the day after I brought it for....£400 so no big deal if its a total loss when vag-com is plugged in. Have looked up on a replacement engine if needed. Anyway..pm sent.
 
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