EdgeminSH

I got my car running boosting and running great but the one thing i noticed is my BOV wont go off completely. its a BLITZ, It just flutters. I loosned it all the way, and then tried tighting all the way and no difference. I have it T'd in my FPR vacumm hose, and my boost guage is t'd in there as well. Whats going on?

Chacko

Can you see the valve when its in idle? At idle the valve should be partially pulled up (there is an actual piston like device that slides up and down inside the BOV) if its not partially pulled up at idle then you've got a vacuum source problem.

You can try pulling it up and down with your fingers, it might be a lubrication problem (if it is difficult to slide up and down call the company that manufactures the BOV and relubricate it) the other suggestion is that your spring needs to be stiffened out.

The looser you go, the less tension there is on the spring. This in turn means the BOV will open up more frequently and easier.

When you say it won't go off completely - is it just not sounding the way you expected? How much boost are you running? And where did you hook the vacuum for the BOV off of?

EdgeminSH

Im running 7psi its T'd in to the fuel pressure regulator. should i T it in somewhere else? because i also have a boost guage T'd in there

Chacko

no thats fine, the only other place you could try is trying it with the turbo charger's nipple (for the exhaust actuator). But it sounds like you might have your BOV to loose and its leaking air all the time. What you should do is prop open the hood, set the car in neutral with the e-brake on.

Turn the engine on and rev it using the throttle body actuator (its a spring looking device attached to your T-Body with a cable that runs through to the gas pedal). Watch the valve inside the BOV. It should be drawn in when the engine is reving up and as soon as it hits neutral it should be opened up. If its not opening up then your spring is to stiff and you need to cut it or try lubricrating that valve itself.

If its staying open then thats why you're having problems, all the air is leaking out of it! And you need to stiffen the spring.

EdgeminSH

i dont think the air is leaking out of it... the car flies. i cant get it to go off when reving it. how would i go abouts lubricating it? or cutting the spring?

Chacko

ok first off. Remove the BOV from the car. And see if you can disassemble it. BOVs are very simple devices. Its just a piston that moves inside of a smooth cylinder, and when it slides up and all the air rushes out it generates a whistling sound.

What you waant to make sure is that the valve is sliding up and down smoothly. At idle it should be partially open (or fully closed depeneding on the design) as soon as you hit vacuum though the valve should be pulled up, allowing all the air in the charge pipes to be sucked out (this way it doesn't circulate back to the turbo).

What you need to make sure is that a) your valve is easily sliding up and down b) that your spring tension is not interferring with the valve at idle.

If its at least resounding while you're doing normal driving it may be that you're just not generating enough pressure to make noise in neutral (I know that cars generally do not build boost when sitting in neutral they reach around -8 hg/mm or whatever the ---- unit it is) because they need a load to properly propel the exhaust turbine.

Anyways if its resounding like it should while driving, but not in neutral, its probably working properly. You should at least hear some sort of a 'flutter' in neutral. Like I said, if you're really worried turn the car on open the hood and rev the car yourself and watch the valve. While the car is being revved it should fully close, and hten once you release the pressure it should open up and all the air should rush out of it.

To cut the spring you'd have to disassemble it and get a pair of wire cutters, I do not recommend this if the BOV is working while driving.

EdgeminSH

It was not working while driving. it was making a multiple chuffing noise like it wasnt opening all the way. But when i loosned it it sounded the same, and when i tightened it it sounded the same. I will go mess with it take it out see how easy it moves. Thanks for the help

Chacko

run it in neutral and see if the valve is even pulling up in neutral. If it isn't then you need to reduce the tension on the spring as much as possible (this would include even cutting it) there may also be a problem with the vacuum hose itself.

EdgeminSH

It opened when i reved it up.just a little and didnt make any noise. When i push up on the valve it seems to be easy. It dont open at idle, Could it just be a poor vacumm source i have it T'd in to. I dont want to cut the spring and be fucked. how do i oil it

Chacko

you have to contact the manufacturer of the BOV, every BOV uses a different lubricant

Uhm if its not opening at idle or not raising at idle you need to really reduce the tension on the BOV. I would try T'ing it into the vacuum source for your brake booster (leave brak boost un plugged) and try it in neutral again. See if that makes a difference in how it reacts.

Then of course, put the brake booster back on. But I don't think its your vacuum source I think the BOV is just not moving up fast enough.
What kind is it again and if you can, disassemble it and send me pics?