boost problem.....again

[WhiteGTI]

Do the battery thing first Joe.

If the MAF was playing up then the car would not be running well, i.e. a little hesitant, lumpy, jerky etc. But i suppose its worth a go, seeing as its so easy to do!

[RedRobin]

my car doesnt seem to boost past 10psi in 1st or 2nd gear then in 3rd 4th 5th 6th it boosts to 20psi but only when its past 3000 revs!!??

it was in for diagnostics yesterday and no boost leaks were found, and the car seems to be healthy.

ive just been on the phone to the tuning company who mapped my car and they have told me to disconect the battery for 30 mins??? doubt this will do anything but has anybody else hurd or anything like this or can anybody suggest anything?

....Responding as you asked, Joe, and sorry to hear about this problem.

With my boost leak problem I didn't have the 10 psi / 3,000 rpm characteristic and also diagnostics showed a boost leak but not what was causing it. As described in my thread in the Troubleshooting forum, JKM then checked for physical leaks by a process of elimination.

How experienced are your tuners with the 2.0T FSI? Don't their diagnostics include data logging and what shows there?

HTH

[joesgti]

it was in for diagnostices at awesome-gti yesterday, and they know the 2.0t fsi platform very well as you would expect, but couldnt find anything, which got me thinking it may be a cracked turbo like yours.

will report back tomorrow once i have tried the battery thing,

the cars still rapid and doesnt feel any slower, its almost like a v-tec

[RedRobin]

it was in for diagnostices at awesome-gti yesterday, and they know the 2.0t fsi platform very well as you would expect, but couldnt find anything, which got me thinking it may be a cracked turbo like yours.

....I didn't realise it was Awesome - Thought I read celtic-something.

A cracked turbo/manifold would probably show as a boost leak in diagnostics, so you appear to be safe from that.
 

[joesgti]

it was in for diagnostices at awesome-gti yesterday, and they know the 2.0t fsi platform very well as you would expect, but couldnt find anything, which got me thinking it may be a cracked turbo like yours.

....I didn't realise it was Awesome - Thought I read celtic-something.

A cracked turbo/manifold would show as a boost leak in diagnostics, so you appear to be safe from that.
 

celtic tuning were the mapping company, 

[jonnyc]

Have you checked your DV??

[cossy]

Have you checked your DV??

Good point, I would check it also.

[joesgti]

DV was taken off and re-fitted, all is good with the dv (unless a forge one can break inside?)

theres no boost leaks! 

[RedRobin]

^^^^
Yep, DV and PCV. They were the first things JKM checked once we knew there was a leak.

But surely the data logs would show a leak (higher % boost requests to compensate) if the DV was faulty?

Have Awesome either been on the rollers or taken your car out with a laptop?

Did Awesome check the Forge DV seal?

[jonnyc]

^^^^
Yep, DV and PCV. They were the first things JKM checked once we knew there was a leak.

But surely the data logs would show a leak (higher % boost requests to compensate) if the DV was faulty?

Have Awesome either been on the rollers or taken your car out with a laptop?

Did Awesome check the Forge DV seal?

So you have the forge DV??

Did you check the O-ring and make sure the piston was well lubricated, if it were to stick then you would leak boost..

Could be worth running some requested and actual boost logs on Vag com..

[cossy]

I cant speak for your map but my bluefin on the "Max Map" doesnt boost much in 1st & 2nd.

Low power map it does though

[joesgti]

^^^^
Yep, DV and PCV. They were the first things JKM checked once we knew there was a leak.

But surely the data logs would show a leak (higher % boost requests to compensate) if the DV was faulty?

Have Awesome either been on the rollers or taken your car out with a laptop?

Did Awesome check the Forge DV seal?

So you have the forge DV??

Did you check the O-ring and make sure the piston was well lubricated, if it were to stick then you would leak boost..

Could be worth running some requested and actual boost logs on Vag com..

so the forge DV needs lube? has anybody else reported that they stick? PCV....whats that?

[tony_danza]

I think if it was anything broken, then it wouldn't be making boost in any gear?? You said the rest are fine 20psi over 3000rpm, right?

Try the battery and we'll go from there, bit by bit and we'll find it. No sense stripping the car, having a play with everything, fixing it and not knowing which one was at fault.

Sounds like you could do with someone VAGCOM savvy too for some live logging.

[joesgti]

I think if it was anything broken, then it wouldn't be making boost in any gear?? You said the rest are fine 20psi over 3000rpm, right?

Try the battery and we'll go from there, bit by bit and we'll find it. No sense stripping the car, having a play with everything, fixing it and not knowing which one was at fault.

Sounds like you could do with someone VAGCOM savvy too for some live logging.

yea, i could do with vagcom (if anybody lives near by and wants beer tokens?) will do the battry tonight and repot back here.

if this is any good  then i had a race spirited drive (on my own race course in fiji) with a clio 197 last night and i wiped the floor with it!? so the cars still making good speed 

[RedRobin]

....

But surely Awesome did some data logging!!??

PCV = Positive Crankcase Ventilation one-way valve and quite a common failure it would seem.

Take your pick : -
http://www.google.com/search?hl=en&client=safari&rls=en-us&q=PCV+valve+Mk5+GTI&start=10&sa=N

But perhaps you would hear something if it failed. Also performance would doubtless suffer more globally. I dunno, I haven't read it all.