Still a lack of boost, what else to do?

[dub17]

so i've been having a lack of boost for many weeks now, around 6/7psi when it should be more like 20, ive done the N249 bypass, replaced MAF, removed the pipe the goes from N75 to the actuaor just to test that, ive just removed the front bumper to look for loose or split hoses but everything seems to be in order (bumper is still curruntly off the car) just wondering what else i could try, i had two fault codes, one for MAF and one for N249 (16486 and 17695) i deleted the codes before i done the bypass and replaced MAF so maybe the codes came back, would that require me to delete them again if they did come back to maybe get it working again? what else could i do to try and sort this out? it's really getting to me! and help would be greatly apreciated, thankyou.

 

[Pew.]

Deleting the codes wont automatically make whatever the code was for work again.

Do a scan and see if the codes are there first, if they aren't then there is obviously another problem.

Is it like a surging boost will it just not go passed 6/7 at all

 

[tom w]

Have you checked all the vac lines too ?? And replaced the n75 hose ??

 

[dub17]

i put the n75 hose straight back on, only removed one side of the hose to test it for a little run as thats how you test if its the n75 that is causing the problems, apparently. yeah the boost wont go past it at all. erm i cant say i've checked vac pipes, i dont really know where to look? just checked all the hoses that are to do with boost.

 

[tstrahonja]

Have u looked at your actuator threads? There should be 11-14 visible threads from top of actuator rod..
If u removed the hose that goes from n75 to actuator and still havent got boost then i think ure def have some actuator/wastegate problem.
Try pulling actuator with ur hand..it should be very very stiff.

 

[dub17]

there are 12 threads at the top of it. and it is not that easy to move it.

 

[dub17]

i think boost varies from like 3-8psi, but never more than 8. i could be wrong.

 

[yellonvi-R]

Is your car mapped? These only run around 6-8psi standard.

 

[dub17]

mapped to 190.
i got 9 codes just come up, erased them, took for a run, nothing, plugged it back in and one code remains (16795)

 

[Jaycupra51]

There is a post
17965 resolved-with pics

 

[Chambers_CUPRA]

Take it you got a boost gauge? Have you check the pipe work or the gauge it's self?

 

[dub17]

i have a boost gauge, check it for what? i know its not boosting to what it should be because i can feel the loss of power. or you saying that's where there might be a leak?
yes jay i have checked that pipework and it all seems to be okay there. im going to buy a few metres of hose tomorrow and get rid off all the factory fted stuff, what mm will i need? 6mm internal? (tubing for n75/n249 ect) the 6mm i used for n249 bypass seemed a tiny bit big.

 

[Jaycupra51]

That's where ur problem might be its only 4mm
Mate throw the 6mm away

 

[dub17]

i did the bypass to try and get it boosting normally but didn't make a difference, still only very very little boost.

 

[Jaycupra51]

Have u checked ur intercooler I would have
A word with bill or even Jabbasport see what
They think
Have u checked ur egr valve

 

[tom w]

Vac lines I used 3mm tighter fit !

 

[Chambers_CUPRA]

6mm is to big 3mm standard or 4 I'd your running big psi.

Yeah ment the pipework to the boost gauge going though the car etc and easily get split.
My mate gauge its self broke up causing boost leak took him ages to find it as it was the last place anyone would think to check as it's so rare lol

 

[Chambers_CUPRA]

6mm is to big 3mm standard or 4 I'd your running big psi.

Yeah ment the pipework to the boost gauge going though the car etc and easily get split.
My mate gauge its self broke up causing boost leak took him ages to find it as it was the last place anyone would think to check as it's so rare lol

 

[Chambers_CUPRA]

Egr valve is a very good shout tho if you've done the bypass

Seen a few people leave that pipe off doing the bypass if the sai is being left on!

 

[Jaycupra51]

4mm forge recommended to me