Ok still a big problem, if I go over a certain mph and have given it a boot full, then leave it to cool down on tick over turn it off then the next day it's in limp mode! Turn it off leave it a bit then it's ok again! It's driving Me crazy, so far I've had a smoke test no leaks, cleaned throttle body, brand new 're circulating valve forge, New n75 valve, New Bosch maf sensor, had the codes written out 17705, New vacuum valve, n249 bypass, I just don't know what else I can do, please help

Drop tested the battery? Mine forever did it even though it started it wasn't getting enough voltage so went into limp constantly

Edited 19 August, 201411 yr by guss84

Is that possible bud, the battery has never failed me starts first turn of the key ect

Should be able to get a free battery health test at most of the big places that sell them. 

I had a similar issue with the MAF sensor. But wouldn't happen all the time and only did it when you went over a certain speed. I confirmed it by logging with VCDS and driving with the MAF unplugged once it had gone into limp mode.

But like FUBAR said get the battery checked as well

Yea I think I will get it checked peeps, my maf is brand new two weeks old didn't make a difference when I changed it, what about the map sensor on the intercooler would that maybe cause it? And thank you for all replies

My car is modded also with, forge tip, forge cold side 're location kit, cat back system and 200 cell cat, 2.0 coil pack kit, cai kit, custom 're map done on the rolling road, forge 008, one step colder plugs,

My one used to do this cleaned maf etc turned out to be water temp in the end bought from dealer not cheap at all for what it is but cured the running issues.

Mine started every turn but it was spent and when had it tested was knackered but since fitting a new battery it has never missed a beat

Edited 20 August, 201411 yr by guss84

Have you had the car scanned with VCDS for faults, not just a generic reader.

Depending on your location I'm happy to scan your car with vcds

Codes were, p1297 and p0420

Both codes point towards a split breather pipe if you ask me

I'm just having a battery test now so see what that brings, I have had a full smoke pressure test and came back fine no leaks

I'm sure my turbo isn't spinning up as fast as it use too

In low revs you could hear the turbo spinning up but be now you have to give it a bit before you can hear it and Feel it, not sure if the n249 bypass would of caused that?

N249 wouldnt cause that.

Just had the check alternator is good but battery needs a big charge

New battery going on!

Doubt it will stop your limp problem though

I don't but it's worth a shot, it was the original battery on it lol, I just don't know what the next step is I'm lost on it

Get some cheap carb cleaner and with the engine running blast all the pipes under inlet manifold.

Is that too see if anything is split

Yep. I know youve said you had a smoke test but just to be double sure because those codes are linked and in most cases its the breather pipe system

Is carb cleaner the best one to use