• Guest would you be interested in CUPRA or SEAT valve caps? let us know in the poll

  • Welcome to our new sponsor Lecatona, a brand dedicated to enhancing performance for VAG group sports cars, including SEAT, Audi, Volkswagen and Škoda. Specializing in High Pressure Fuel Pump (HPFP) upgrades.

Weird Boost.

xJmagik

Active Member
Sep 17, 2010
66
0
sussex
Alright Guys,

i noticed recently that my car is not holding boost very well. Im running stage 2 on a Ko3 but when i give it some throttle my car spikes to 1.5 bar (22psi) but as my revs increase and it gets towards the redline its seems to of drop of to around 0.9 bar? is this normal or do you think i have a boost leak? (recently changed my the majority of my vacum lines)

Also i noticed this morning as i was driving to work. my car would be boosting as normal/same as above then all of a sudden i would accelerate on the throttle, my boost would increase to around 1.0 /1.1 bar then suddenly drop of down to around 0.7/0.8 and keep decreasing (3500/4000 revs) i could hear from my engine bay like a sucking/leaking vacum noise, but then i got in my car to go to lunch and it was back to normal for around 10 mins then did the same thing. any of you got any ideas what this could be?

thanks
 

kyle'87

Modding Disease
Sep 15, 2008
868
0
Ruislip
I know boost will tail off as you go up the rev range as to how much depends on the map and the performance of your turbo.

maybe your DV spring is getting weak and releasing some pressure prematurely when you poke the throttle althought I doubt that.
 

xJmagik

Active Member
Sep 17, 2010
66
0
sussex
yeah i know it supposed to tail of a bit but think mine seems to quite a bit. im running a Revo stage 2 map. does anyone else's seem to drop of quite a bit?

mm yeah maybe but i have a fairly new forge 007p dumpvale so hope not.

i did notice the other day that i was feeling round the base of my forge tip and it seemed quite lubricated/oily. do you think it could be my tip leaking?
 

mc funbot

its a beast its got boost
Jan 29, 2010
1,473
4
sunny kettering
www.seatcupra.net
have a clean up ive had a few locasl guys come to me with the same thing it can be down to may things i dont think it is your dv. looked in to stuff like n75 have you got a split vac pipe is your maf ok? way to check your maf unplug it and try it. see if it still happens if not you no the problem, let me no how that goes for you.. dont drive it to much disconected!!!
 

cuprawill

Turbo lag is foreplay
Nov 20, 2009
703
1
That's about right for a k03 they really struggle up the top end due to size.
 

20vturbocupra

Active Member
Mar 25, 2012
206
3
Exact same happened to mine when I had k03 now I'm in process of k04 conversion this seams to be normal and it's no wonder when you see the size of the turbo inlet housing lol it's tiny
 

xJmagik

Active Member
Sep 17, 2010
66
0
sussex
Yeah i have recently changed my N75 Valve so ill rule that one out. My cars just got an EML light on this morning so I'm going to take it to a mates garage after work and plug it in to see the problem. think it could be the MAF sensor from reading around.

If it is MAF related does anyone know/recommend where to purchase one from?

looks like i might have to look into up rating the turbo then ;) what are the Ko3s like?
 

mc funbot

its a beast its got boost
Jan 29, 2010
1,473
4
sunny kettering
www.seatcupra.net
if you need a maf get it from trade part servises aka TPS other places just have crap its that simple been there done that! a ko3s dont get that much more out of them but thats my view.. get a ko3 set up well on stage 2 an they are super fun to drive myn was awesome!
 
Nimbus hosting - Based solely in the UK.