Loosing Boost

[MrNailer]

hi guys i bought my cupra about 4 weeks ago, And since i have done n249 bypass followed by a forge split R on full Circ, With n75 valve a J valve was ok for a couple of days then stop boosting and now after 2-3 mins of starting car and going somewhere it just stops boosting even on motoway even booting it!!!

i i put origanal dumpvalve back on and n75 one back on!

i been to garage and had it on code reader and here there are

Maf sensor, charge pressure positive devation, coolant temp sensor?

whats cutting my boost off been like this for 2 weeks sick to death! Anyone help me?

 

[R4cup]

U might want to check u maf meter as this also happened to my cupra

 

[MrNailer]

did it cut you boost then?

 

[MrNailer]

anyonw have any idea ???

 

[JJ_arosa]

mine is doin it aswell and iv just fitted a new bosh maf sensor still the same

 

[MrNailer]

what the hell is it then ive just orded sensor and i have replaced n75 valve what can it be if its not maf sensor?

 

[jcc-gttdi150]

If you're remapped, it could be a loose join between the pipes. Happened on my last Golf when it was mapped, to the extent it blew the pipe off!!! Jubilee clipped it back in place and the car felt transformed. Had been struggling for mpg for a while too

 

[MrNailer]

no not mapped lol sick of car

 

[MIkey kc]

it your maf for sure! you also need a new coolant temp sensor!

if you car is dead slow and you unplug your maf and it seems to go alot quick that proves its your maf

 

[MrNailer]

i spoke to scotc1088 who lives near me and he said same about upluged it and had no boost at all but ill going to try it tomoz i meanb ive been out all night been boosting for over 3 hours flat out fantastic but what i did was take the air pipe out of air box so i think ur 100% right and i have fitted temp sensor today and also orded maf sensor 107:-( lol am going to try and unplug it hope this works!!!