BOV will not operate

[BlackMetal]

This also doesn't explain why the other valve I bought doesn't work either. Seems like it's the car.

 

[BlackoutDrunk]

I took off the little attachment that came inline on my BOV and it wasn't a checkvalve. Air flowed freely both ways through it. I didn't think to check if it was a filter though. ...and I too lost it.

 

[BlackMetal]

Well I tried one of the "fixes" I came across on a DSM forum, which suggested drilling a hole through the casting, connecting chamber C & B. The idea being the surge of air would actually be able to reach the bottom of the diaphragm and push it open. Buuuut now the valve stays open all the time. Might work if I had it recirculating but that's not gunna work for an atmospheric BOV.

So I don't know what to think. That would seem to prove that the diaphragm still works, engine vacuum was pulling it open and holding it there. A dot of JB weld will close the hole I drilled, but then I'm back to step one.

The valve is supposed to open when there is a pressure difference between chamber A & B. Chamber A is the side of the diaphragm that sees vacuum. When the throttle closes, the engine goes back to vacuum but chamber C & B should be experiencing a rush of pressure, which is supposed to help push the diaphragm back. It seems like drilling the hole makes MORE sense than without it, how the hell does chamber B ever pressurize if it's sealed off? So I thought this all made sense, but somehow the valve is staying open at idle. Don't understand why, all three chambers should be under vacuum at idle, meaning no pressure differential, and no diaphragm movement.

And yes I put the spring all the way back to TIGHT thinking I needed to compensate for the hole I drilled, but that wouldn't keep it closed either.

 

[BlackMetal]

I think I'll just save up for a tial or one of those fancy Synchronic ones.

 

[BlackMetal]

Ordered a new knockoff just to put my curiosity to rest. If it still doesn't work then something is screwy.

 

[Louie L.]

With the soft spring i made for my knock off, the valve will stay open at idle. With the stiff spring the valve stays shut. As soon as I hit the gas with the soft one the valve closes.
When the boost hits its stays closed. Of course this is on a race app which can handle an open valve .

I have seen the procharger valves bounce on other cars while they idle.

 

[BlackMetal]

With the soft spring i made for my knock off, the valve will stay open at idle. With the stiff spring the valve stays shut. As soon as I hit the gas with the soft one the valve closes.
When the boost hits its stays closed. Of course this is on a race app which can handle an open valve .

I have seen the procharger valves bounce on other cars while they idle.

Yeah I did realize that I forgot to blip the throttle and see if the valve would at least close then. It was still running way too rough with it open at idle, but maybe I could have adjusted the IAC and got it to run better.

We'll see. The place I ordered from has a good return policy. I won't use the new flange or anything, just clip on the new valve and see if it works or not.

I'm starting to think all I really need is a much ligher spring, but that's still strange because at one point it DID open with whatever spring is in here.

 

[BlackMetal]

I found a bit softer spring in my basement. Too bad I already ordered the other BOV. Letting JB Weld cure in the hole that I drilled and I'll test this spring out tomorrow.

 

[BlackMetal]

Aaaand with the slightly lighter spring, the valve stays open at idle. So then the original spring was just enough to hold it closed. Then I don't understand why it won't open when it's supposed to.