Loss of Boost?!

[adamf]

Hello All,

Iv had a little problem for the last couple of weeks that i cant get my head around. Every now and again, my GTI is loosing its boost for some reason.. It seems to be really sluggish and not spooling up like it should (put foot down WOT and nothing really happens - My GF's Polo 6n could run rings around it and thats only a 100bhp...  ) Exhaust seems loader than usual but no power and cant hear it spool up as it usually does. Feels like im driving a 1.2 clio :-( but then all of a sudden it will come back on and pull hard again as it should. Sometimes this can last 10 mins or hours untill it comes back to normal.

A bit of background info on the car. It's a 05 GTI with 50 something K on the clock, Stage 1 Map, non res miltek cat back, forge diverter valve and pipercross intake. These are the main performance mods (well i wouldnt call the filter a real mod but it came with it lol). It is due a service now and is due the coilpack recall and a software update from main dealer...

I thought maybe the Forge DV or actuator may be getting stuck open and causing it not to have any boost pressure???...

Has anyone come across this before that could possibly help me in getting my power back permanantly 

All help appreciated 

Adam

[edd666999]

if it hesitates its more than likely the coil packs, that's where id start. if still have issues look http://www.mk5golfgti.co.uk/forum/index.php/topic,120.0.html And find your local guy (pm him and offer him beer) that can scan your car for errors.

N75 valve IMO is somewhere id look after other possibilities

[adamf]

It doesnt hestitate...theres just no power. put ya foot down and nothing hapens?..

but then i could turn the car off, go out an hour later and it will be fine...

[Roberto236]

Hi,
I've got a 2008 Mk 5! GTi and it's been doing the same thing. It loses power and goes into a sort of limp mode. It wont rev up over 500 rpm and it wont move. Turn it off and on again and it's fine. It's been doing it for quite a while but it's getting worse. 5 times today! My main dealer has found no fault as yet. They are going to look again next week so I'll keep you posted.

[adamf]

Thanks mate. Its a bit different though. It doesnt seem to be in a limp mode. It still revs all round the clock but as if someone has taken off the turbo. just reallly flat and doesnt lanch you into your seat. It doesnt hesitate either, literally like the turbo has been taken off... just smooth powerless revs 

No EML either. Will have to plug it into VAS at work and see what that says when i get a chance.

[56OctyVRS]

Sounds to me like a faulty MAF sensor. Hopefully a scan will reveal a fault code for you

[adamf]

It is all a bit strange...maybe a new spring is needed in my Forge DV?.. like its staying open and not allowing boost pressure to build up. Will scan it when i get a chance at work...

[Top Cat]

sounds like a DV

Why do i feel like a forsale thread is just about to appear. 

[percy]

I also have had this experiance with mine on an 05 plate, so i will keep an eye on this thread to see if anyone can solve it. Would changeing the plugs help? As i thought about getting some of thos ngk iridium ones, Regarding the coilpacks i thought about changing them aswell as mine arent genuine ones as these were changed by the last owner. Where is the best place to buy some new ones from?

[adamf]

Just a little update and a strange query... My battery started to die so I bought one yesterday. Engine light went out directly after fitment and my boost is back and running like a dream... Could this of affected it by throwing it into limp mode due to not having the correct current from the battery therefore cutting the boost?.. or is this a massive coincidence and will it go back to its problem in a few days?...

[Andy]

Just a little update and a strange query... My battery started to die so I bought one yesterday. Engine light went out directly after fitment and my boost is back and running like a dream... Could this of affected it by throwing it into limp mode due to not having the correct current from the battery therefore cutting the boost?.. or is this a massive coincidence and will it go back to its problem in a few days?...

guessing with changing the battery will have reset every thing..fingers crossed it cures it

[percy]

Ive had a similar problem as iam running the forge dv so gave it a service and also renewed the solinoid that the forge kit comes with,so will see how it goes now for a while! Also coilpacks were replaced earlier but didnt make a difference!also plugs!