99AccordTurbo

I drive a auto Accord 6th Gen with Fmax stage 2 turbo kit/ 8psi

When i am boosting around 5 psi at mid throttle my car blows off and builds boost at the same time. Occurs at high and low speeds but at mid throttle.

Does anyone know what this could be causing this????

Do I need to tighten my blow off or something???

egturbo

maybe when its shifting? lol bump someone help this automatic turbo driving dude post pics.

Boltz

Sounds like there is something mechanically wrong with your BOV.

If what I understand is correct, then the I/M pressure (vac line) going to the BOV is what stops the BOV from releasing its pressure. The bov is supposed to open when it either isnt boosting or reads vacuum. If your BOV is opening when you are building boost, id say there is something wrong with the bov.

flip1199

my guess would be because the tranny is shifting.

99AccordTurbo

It definitaly blows off when shifting but when i accelerate over a bridge or something around 3000rpms it does it...i am not that big of a dumb *** i know when the car is shifting and when it is not. I was going 70 on the interstate and went over a bridge and the cruise control kicked in when the car hit 3000rpm and about 5psi of boost hit started blowing the boost off and building it then blowing off and then building it, over and over, you get it.

flip1199

does it do it when your not in cruise control?

pngfolife

Same problem here. It happens as boost builds in the charge pipe while you are at part throttle right? The BOV diaphram is seeing manifold boost pressure but the valve face sees more boost than that and opens, relieves pressure and shuts until boost builds up again and opens again, causing a sort of shuddering while throttle remains constant. If this happens, either open the throttle more or just let off to a throttle position that does not allow boost to build.

99AccordTurbo

Perfect explanation. Well thats what i do now just let off or speed up. I was just wondering if there was a fix for it.

It happens without cruise control also!


Modified by 99AccordTurbo at 12:27 PM 8/10/2004

pngfolife

Wanna fix? Get a different BOV with a stiffer spring. Do you have a single diaphram HKS BOV?

99AccordTurbo

No, the new Turbonetics Raptor came with my kit!

99AccordTurbo

bump

Chris F

Well, as long as it's closed during WOT it's all good!

If you can adjust that BOV tighter it would help.

I'm gonna wager that all BOV's do this some, but they're not always audible. I never hear my type-S BOV unless I'm going from some RPM back to idle, it squeeks just as it gets to idle as it's shutting again.
EDIT: Also I obvioulsy hear it when shifting under boost.

pngfolife

Just increase spring pressure by turning the adjustment screw clockwise but don't go overboard or the valve won't open or only open very slightly and will cause compressor surge.