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New to this forum, looked up every possible solution on here and couldn't find anything, so sorry if this has already been addressed somewhere.
So I bought '08 GSR a couple months ago and after driving the last few weeks I've noticed that if I brake a little too hard, the engine dies, also happened once while turning. This morning also noticed that braking with clutched pressed in, the RPMs would dip between 250-500. I've checked what I could at home and everything looks to be in working order. Had an '05 STi and a '14 Camaro SS and never experienced this problem before.
Thinking it could be a throttle body problem, but not sure. If anyone has any solutions or suggestions it be completely appreciated.
are you in neutral with the clutch in and braking?
No, it's usually in gear
Originally Posted by hoobastnk90
Hmmm well are you getting any SES lights? Is the car tuned? What mods does it have?
Did get a SES once, but it cleared itself and the car sat turned off for a couple hours. It is tuned and modded, but not sure of everything on it so far. Most of what I could tell is a downpipe, CAI, had a aftermarket boost controller and solenoid that wasn't hooked up with the stock unit still installed, but whatever reason the vacuum hoses where cut. I'm slowly replacing and fixing things, but trying to narrow down this problem first.
You definitely have a vacuum leak. When you brake the booster uses vacuum to assist in braking and will cause issues if there's a leak/disconnected hose. Check the boost controller hoses that you mentioned and also check the vacuum line that runs from the FPR to the intake manifold as it's known to pop off.
You definitely have a vacuum leak. When you brake the booster uses vacuum to assist in braking and will cause issues if there's a leak/disconnected hose. Check the boost controller hoses that you mentioned and also check the vacuum line that runs from the FPR to the intake manifold as it's known to pop off.
^^^ Do this... It definitely sounds like a vacuum leak. If nothing is "visible" at first glance regarding any loose hoses or hoses that popped off. I'd check every inch of the vacuum system to make sure there isnt an area where maybe a vacuum hose cracked open, etc... That way you can eliminate that scenario and move on to the next possible solution. GL
Man well sounds like your problem is either with the tune or with the mess of cut vacuum lines do you have anyway to run a data log?
Not yet. Had a BAFX bluetooth OBD2 for my Camaro and tried it on my Evo and whatever reason doesn't work so can't check any codes til my new scanner comes in.
Thanks for the suggestions, completely forgot about the brake booster. Have about 6 feet of vacuum hoses laying around so i'll give it a try this weekend and hook the boost controller back up til I can swap with a Grimmspeed.
So went out and checked using the diagram and immediately noticed the dual boost solenoid lines are just completely missing (with one being cut like i mentioned)....seems to make a lot of sense now
Lol agreed, do you know where I can buy a complete kit to replace it like in the diagram or just build from scratch? Seems like a lot of places cater more to the STi these days.
