boost droping down soon as it hits 20psi!

[p34ch3y]

right ive had this problem for quite a while now and its starting to do my nut in

il try explain whats happning the best i can

first of all ive checked for leeks and none found
the dv is a forge 007p wich it had a sevice last week with the sevice kit from forge so new o-rings all round new piston and plenty of grease

right whats hapning is,and this dos not happen all the time but enuf to piss you off ,so when i boot it and get it on full boost its gos up to 20psi and instead of droping down nicely to lets say 12/13psi it lets go strate away,so it flick strate down to 11psi and it sounds like it half dumps and then it sound like the dv is left slightly open as if it a realy realy long dump,basicly you can hear all the air rushing throuh this is all with my foot on the loud pedal all the time im not leting up at all

any idears....i did think that i mabie need to upgrade to the yellow spring in the 007 but im very unsure

any help would be grate

 

[ibizacupra]

any deviation codes thrown?

 

[pj1985]

Do you have the n249 bypass done?

 

[p34ch3y]

any deviation codes thrown?

no none

Do you have the n249 bypass done?

yes i do

 

[cupra drew]

off topic but what are your 8000k hids like am thinkin bout them instead of the 6000k thanks

 

[SeanyK]

It's a tough one mate, I wonder if it's similar to what I experience at the moment (standard map it did it as well)...

Put your foot flat down in 3rd or 4th gear, sometimes even 5th, when it hits about 3k or so revs you can hear the dump valve dump air even though you've got your foot flat down without releasing the pedal.
It kinda pushes you back and then continues to go as normal... But if it were two cars next to each other with the same power doing the same, the one that didnt do that would be pulling away... Thats the way to explain it, as it's a performance loss, as well as pretty much strange!

In my case im 99% sure its the N75, as I borrowed a friends N75 at the weekend, and briefly tried it, and it didn't happen...

Have you changed your N75? I'll be able to let you know the full outcome on Friday when I fit my replacement N75, i've gone for a N75 J valve, my existing one is a N75 'C'.

 

[DaNnY_LaD]

Is this a k03 or k03s?

 

[p34ch3y]

It's a tough one mate, I wonder if it's similar to what I experience at the moment (standard map it did it as well)...

Put your foot flat down in 3rd or 4th gear, sometimes even 5th, when it hits about 3k or so revs you can hear the dump valve dump air even though you've got your foot flat down without releasing the pedal.
It kinda pushes you back and then continues to go as normal... But if it were two cars next to each other with the same power doing the same, the one that didnt do that would be pulling away... Thats the way to explain it, as it's a performance loss, as well as pretty much strange!

In my case im 99% sure its the N75, as I borrowed a friends N75 at the weekend, and briefly tried it, and it didn't happen...

Have you changed your N75? I'll be able to let you know the full outcome on Friday when I fit my replacement N75, i've gone for a N75 J valve, my existing one is a N75 'C'.

yea keep me updated please

Is this a k03 or k03s?

std ko3 mate

 

[tom w]

what map are you running ? mine only boosted to 20psi when i had a leak between the charge pipe and the n75! as mine only boosts to 14psi right to the red line! with a jabba map

 

[Reuvers]

what map are you running ? mine only boosted to 20psi when i had a leak between the charge pipe and the n75! as mine only boosts to 14psi right to the red line! with a jabba map

? your map boosted higher with a leak than without one?
And isn't 14psi quite low?

 

[acidstrato]

p34ch3y can you vag com it, record actual and req boost and stick the data into a line graph? curve of the boost would be interesting to see

 

[p34ch3y]

what map are you running ? mine only boosted to 20psi when i had a leak between the charge pipe and the n75! as mine only boosts to 14psi right to the red line! with a jabba map

stage 2 custom jabba map allways been 20psi mate even my 1st cupra with a stg2 jabba map on it was 20psi your car dont sound right 14psi is bad

? your map boosted higher with a leak than without one?
And isn't 14psi quite low?

i havent got the full vag come mate

 

[SeanyK]

Just to give you an update - I fitted the N75 J valve and it now boosts much better, i'll clarify it 100% tonight but tried it earlier and no hesitant boosting anymore.

Will have gauges fitted this weekend or next, so will be able to give exact psi's then.

 

[p34ch3y]

Just to give you an update - I fitted the N75 J valve and it now boosts much better, i'll clarify it 100% tonight but tried it earlier and no hesitant boosting anymore.

Will have gauges fitted this weekend or next, so will be able to give exact psi's then.

fingers crossed

 

[tom w]

? your map boosted higher with a leak than without one?
And isn't 14psi quite low?

yeah i thought so too , and yeah it boosted higher when it blew a pipe off the n75???????
help anyone!!!

 

[SeanyK]

yeah i thought so too , and yeah it boosted higher when it blew a pipe off the n75???????
help anyone!!!

Blew a pipe off the N75? Never seen that before... Have you put jubilees round each connection of it?

I junked the existing pipework and replaced it.

I'd say it might be your N75 as well mate.

 

[tom w]

well i have now thats when i noticed it
n75's how much do they cost?

 

[tom w]

could it have anything to do with me running a ko3s not a ko3 ? i will try my spare n75 tomorrow then sean if so ,what psi are you running at on a jabba stg 1?? just so that i have a comparison

 

[SeanyK]

Hi mate, i'll get the part number for you tommorow as im out at the moment.

But the N75 cost about £49 from the local Audi dealer.

Im not sure what psi im running as I haven't hooked up my boost gauge yet, but hope to do that either tommorow or next weekend.