something abit odd..any help?

[redgt]

i pickd up my car on saturday morning, it felt very fast (went from a C2) then if seemed to slow down abit (thought i was getting used to the speed)
i fitted a boost guage, but the engine light came on, so i unplugged the battery for 5 min, everything was fine, light went out etc. took car for a spin, and straight away it felt really fast again. i checked boost guage, it was boosting up to 15psi. stayed like this for a day or so, then last night, i noticed it slowed down abit again, checked boost, and no matter what i do it wont got over 5/6psi.

any idea whats going on? not sure about how the cars work etc yet, is my car re-mapped?

any 1 got any idea, its kinnda confusing me now

 

[Martyn]

Sounds like soft limp mode due to overboosting. You need vag-com to check the fault codes logged in the ECU.

 

[flashbsd]

yep quite a common thing to happen, dont be put off and disheartened by it

 

[redgt]

soft limp slow the car down?or will it of seemed faster because of it over boosting?

gonna ave to buy a lead for vag com i think

 

[Craig!]

What mod's does the car have?

 

[redgt]

just a forge 007 from what i can see engine wise




heres a quick vid i took the other night of the boost guage, its pretty bad (jumpy) but it gets up to 15psi a couple of times..
need to take it on a motorway and get a proper reading i think..


http://homepage.ntlworld.com/c.appleby1/MOV00012.3gp

 

[Russ_20vt]

If your car was remapped then it would be fast for the first 5-10 mins or however long it takes for it to go into limp mode. Restarting the car would reset the limp mode so in sense everytime you start the car it should be fast.

However you say its normally 5/6psi which could be meaning its hitting limp mode straight away by a dodgy N75 valve by making the car overboost or something more serious. Or your car could be standard and just be overboosting and then hitting limp mode.

I reckon you car is remapped but its hitting limp mode as soon as you start up but on the odd occasion it doesnt and this is why your experiencing the 15psi.

Its a weird one but you need vag com to tell.

 

[redgt]

what happenes exactly when you hit limp mode?

 

[redgt]

what the n75 valve?

is this what u can bypass ? i read something a few days ago about people bypassing something..

 

[Russ_20vt]

Na thats the n249, the N75 determines the boost the turbo needs to give i beleive.

Limp mode is set at 5psi on my car, bit like hitting a brick wall.

 

[redgt]

whats bypassing the n249 do?

 

[Russ_20vt]

The n249 holds a vacuum that enables the ecu to open and close the DV on request.

 

[Martyn]

There's a massive thread detailing the pros and cons, have a searchy search for more details