Hello,

Symptoms:

Seems to go into limp mode when engine is warm - 5-10mins of driving and it goes poot.

When NOT in limp mode I can hear the turbo spooling up more than usual? sounds lovely but I don't think Im supposed to hear it quite so much..

VAGCOM came out with LOW PRESSURE warning

I assumed it was boost leak so I attempted the cable tie fix on ALL the joins bar one. The one I haven't done is the one at the end, connected to the engine?

Devontopia suggested it maybe sticky vanes, but the car is '06 just past 40k miles, maybe little unlikely? I put a double shot of millers in and attempted to boot, but since its kicking into limp mode quite easily I cant get a spirited run to attempt to 'clear the system'.

I need the car on Sunday for a long trip (2-3hrs there.) and Im not keen on getting there with limp mode.. not sure if its good for the engine, but its defo not good for driving when its top speed is 50-60.. :|

Any help appreciated! :(

Edited 17 September, 201015 yr by JLneonhug

Sticking VNT

Could be a number of things, im experiencing similar problems at min with a brand new VNT15...I've changed the actuator, checked the veins which move freeley, the vac pipe is leak free...things left are the VAC box itself and the MAF sensor...if that doesnt fix it, well, Im stuck lol! So maybe check all of the above?

P.S. Mine returns "Negative Deviation" on fault codes.

Edited 17 September, 201015 yr by VRSDanny

Actuator and checking veins would require me to remove the turbo wouldn't it? I also found some google links on how to clean the VNT turbo.. seems like a bit of a mission! I don't think my skills are that level

I found this link on Sticky VNT..

http://uk-mkivs.net/...s/t/151939.aspx

Is there such thing to "wiggle" on the VRS?

I also found some info on N75 Valve controller. Im guessing this leads to the actuator valve?

http://www.seatcupra...ead.php?t=10170

Interesting read for modifying but doesn't help my situation much atm!

Would putting a boost gauge in help give more information..? If Sticky VNT is the issue I assume it will stay on high boost longer when I put my foot down...? Why do I get LOW PRESSURE fault then?

Edit: No idea if this helps but when in limp mode engine noise is much louder @ anything over 2.5k, sounds as if it has a hole in the exhaust almost. Is this normal?

This sounds like limp mode...when the cars in limp mode is seriously lacks power but sounds much deeper/throatier

I did mine while it was still fitted as keep taking it on n off is a right ballache!!!

UPDATE:

Ok I was having a test drive to pinpoint when exactly it will go to limp mode. (went for a good 1hr drive)

Between 25-50% throttle (depending on rpm/torque) the limit before it wants to trigger limp mode.

Weird thing is that if I build up revs gradually with 50% throttle it seems to be ok with that. Boost is kicking in fine but once it passes 50% throttle it starts to lurch, sort of like switching limp mode on, then off again. I get sudden boost and sudden loss of boost.. its a strange slow motion jolts. If I back off slightly of throttle turbo stays, if I put more throttle it goes into limp mode. :|

Am I explaining classic signs of sticky VNT or something different? (wishful thinking) maybe broken actuator valve or controller (the N75)..?

UPDATE:

Ok I was having a test drive to pinpoint when exactly it will go to limp mode. (went for a good 1hr drive)

Between 25-50% throttle (depending on rpm/torque) the limit before it wants to trigger limp mode.

Weird thing is that if I build up revs gradually with 50% throttle it seems to be ok with that. Boost is kicking in fine but once it passes 50% throttle it starts to lurch, sort of like switching limp mode on, then off again. I get sudden boost and sudden loss of boost.. its a strange slow motion jolts. If I back off slightly of throttle turbo stays, if I put more throttle it goes into limp mode. :|

Am I explaining classic signs of sticky VNT or something different? (wishful thinking) maybe broken actuator valve or controller (the N75)..?

hi if it is the n75 valve you can check if it is the right voltage , unplug with ignition off , turn ingnition on check the voltage at the cables should be same or near enogh as battery, and also check the resistance of the n75 valve itself, should be around 4 but dont quote me (off the top of my head), also have you checked the lil pipe off the wastegate?