variable boost problem
#1
Burning Brakes
Thread Starter
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hi all,
the boost on my car seems to be kind of variable - sometimes it will hit 1.5bar on the factory gauge, other times it will hit nearly 1.8. this is all on the same (relatively long) drive, and is consistent in the same gear (ie WOT in 4th, it might hit 1.8, other times, only 1.5). bad diverter valve? vac leak?
btw, i have an accuboost installed.
cheers,
chris.
the boost on my car seems to be kind of variable - sometimes it will hit 1.5bar on the factory gauge, other times it will hit nearly 1.8. this is all on the same (relatively long) drive, and is consistent in the same gear (ie WOT in 4th, it might hit 1.8, other times, only 1.5). bad diverter valve? vac leak?
btw, i have an accuboost installed.
cheers,
chris.
#2
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Do you still have you cycling valve hooked up in between the controller and the wastegate. If you do, this is your problem. The CV is failing or starting to fail. Bypass the CV altogether. Second possibilty is you vacuum lines are leaking at one or more points.
Also noticed you mentioned that you are using the factory gauge....this thing is very inaccurate. You cannot go by that. Intstall a decent boost gauge to diagnose the problem.
Diverter valve is also a big culprit as it will not last very long at 15 psi. It is good practice to replace it with the 993 valve or better.
Hope this helps
Also noticed you mentioned that you are using the factory gauge....this thing is very inaccurate. You cannot go by that. Intstall a decent boost gauge to diagnose the problem.
Diverter valve is also a big culprit as it will not last very long at 15 psi. It is good practice to replace it with the 993 valve or better.
Hope this helps
#3
Burning Brakes
Thread Starter
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turns out i blew one of the little vacuum hoses off...the one that goes to the diverter valve, funnily enough. hooked it back up and zip-tied it, all is well-ish.
yes i still have the CV hooked up - mainly b/c i haven't gotten chips yet, and i'm hoping that the CV will bleed boost off at higher rpms - if i bypass it, i'm going to get a flat 12psi or whatever all the way to redline, which is nice if i'm chipped (but i'm not...yet).
yes i still have the CV hooked up - mainly b/c i haven't gotten chips yet, and i'm hoping that the CV will bleed boost off at higher rpms - if i bypass it, i'm going to get a flat 12psi or whatever all the way to redline, which is nice if i'm chipped (but i'm not...yet).