Boost Issues on my GC8 Wagon
 

Not sure if this is the section to post this but here goes...

Yesterday I finally decided to change the rest of my intercooler piping. I had changed half the piping before MV10 and was just too lazy to do the rest.

In doing this I removed the front bumper, front lights, Apexi Power intake, dissconnected air flow meter. I turned the front mount around and then put everything back properly as it was after new piping was replaced.

[B]On test drive I noticed straight up that the car was over boosting something chronic.[/B]

My car is a 96 model wagon (EJ207 rebuild) running an Apexi Power FC and Blitz boost controller tuned to 16 psi by GTI Performace centre.

Car just seems to boost beyond 20psi regardless of what presets the boost controller is set too. Even when I turn it to 0 (which should run about 7psi) it still boosts way too much.

Just thought someone on here might have some helpful advice before I make some calls to engine builder and tuning people.

Cheers
Neil.

removing/replacing/re-routing cooler pipes wont cause this.
I'd take a guess and say you've messed up vacuum lines. Either left something off, put it in the wrong spot, squashed it etc. Something along those lines.

WHS^^

Check all the boost control lines, one has either popped off, in the wrong spot or is split.

checked everything and double checked....

No lines were removed / replaced and as far as I can see nothing was squashed or damaged either ....and nothing is dangling around out of place.

Will some of the causes mentioned caus the boost to maximise...shouldnt it be the opposite and resort to factory boost??

If you have a vacuum line off you may not have any boost control at all.
Follow every thing from the boost controller back to the waste gate.
Does the controller make any difference at all?
Will it reduce boost pressure from say 25psi to 20psi or does the car just spool right up no matter what?
Certainly sounds like a vacuum line has come loose.

Im pretty sure the boost controller has no control whatsoever and it spools right up. Ill have another squizz and take for a run and check again.

Boost is controlled by restriction in the lines; if the lines are all fine, then maybe your boost contoller has shat itself?

the boost solinoid has been plumbed in backwards.

reverse your duty cycles on the map, or swap the tubes on the solinoid.

Well ....

Just drove down to Sik Em Rex racing and got him to have a quick look if any lines were unplugged / damaged and all was good.

Next thing I did was ring my engine builder (Tony Flood) and have a chat with him. On inspection of older piping found the pipe that sits on right side of radiator which comes from the intercooler was worn where it sat against the fans and had a small hole in it.

Explained all this to Tony and he had a couple theories:

1. Engine was tuned to older piping with restricted air flow and compensated as such.

2. After reversing the intercooler might have unrestricted some more airflow giving the engine more air to work with.

He was worried tho that there might have been some contaminants in the intercooler and by reversing would of caused them to pushed into the engine. When Im home next week I will pull the intercooler off and give it a furthur inspection to see if theres anything visible that could/may caus some sort of restrictions.

Fingers crossed I havent been driving it the last couple days putting debris and stuff into the engine that would be engine number 3 gone for me :(

Stay tuned ....

You didnt really find out why you boost controller is not working though.
It should still try to limit manifold pressure to your preset 16 psi.
Maybe some one can suggest an easy test for the controller?