I had another thread about this but more or less about vacuum. But i figured i would get a better answer maybe this way. Anyways a few days ago my bov was working after school but then i went home decided that i wanted to try to bosch and ssqv just because i had nothing to do, well i didnt have any tubing to run to the other bov so i said nevermind and took the bosch and put the plugs back in the holes were the bosch is. Not to much longer i had to go some were and on my way home i tried boosting when i let off it sounded terrible, i stopped, and revved it to see if the bov was releasing and it wasnt at all. So i went home and took the ssqv off and put the bosch back on and it works fine. What could be causing this?
Ssqv not blowing off
- Thread starter Fletch124
- Start date
GotTurbos? said:
WHY? ahah. Now lets get back on topic. Ohh and by the way its an ebay ssqv. I took the top part off and for all of you who have done this, the weird black thing on the top "inside" the spring was like half on and half off. Not sure it it has anything to do but yea.
Fletch124 said:
That could probably explain your problem right there, ebay brand. It could have took a dump on you man, but try the things I sugested in the other thread first before you decide to another one. If it looks like you will need a new one, get the name brand. Yeah, it's gonna cost you, but you can't put a price on quality. I think my cousin got his for 200 even.
Have you tried to push the valve open with your fingers? See if something could have gotten into the inside of it somehow and is keeping it from opening.
starscream5000 said:
Did that a ton! Then i put a tiny bit of oil in it thinking maybe it was sticking but that didnt work either..
I'm not sure how the ssqv is built on the inside, but it sounds like there could be some kind of seal busted on it. It could be due to being a knock off brand, they're usually made with cheaper quality parts, you may want to consider buying a new one (if you can't afford the name brand, get another knock off, but I'd say it's just a matter of time before that one would take a dump on you too).
Its pretty obvious that there is a leak on the diaphram side. I sent it to my cousin just so he could mess with it. There are a few fake ssqvs on ebay that come with a 1 year warranty.
Maybe you should buy one of those and turn around and say, "hey, the diaphram broke like 2 days after i bought the damn thing, can i have my refund per the 1 year warranty?". It might work.... Maybe
What I meant was buy a new one and return the old one using the new one's warranty. Just make sure it's a different seller than the one you first contacted...
I think that you have the bov operation a little different in your mind then it really is. Ok, I will explain the best I can.
The bov has a vacuum line to the manifold. When the engine is under boost the vacuum line to the bov is under pressure, and that pressure is equal to the pressure in the intercooler pipes, so it will not open under boost. The pressure at that point is the same on both sides of the diaphragm in the bov, so it does not open. The spring tension is helping keep it closed.
Now when you let off the gas, the intercooler piping is still under pressure, but the manifold now quickly changes to vacuum after the throttle plate is closed, and this vacuum goes to the bov. The vacuum is now trying to pull the bov open, PLUS the boost pressure is now trying to push it open too, and that makes it open until the pressure is released and then the spring pushes the bov piston closed again.
Make sense? Now I explained that because I'm trying to show you that vacuum alone will not be able to open the bov, because in order to overcome the spring pressure you need boost pushing the valve open too. If you were holding the bov it would be easier to push open by hand when vacuum was applied, but you would need to push on the piston in order for it to open.
Now the deal with ebay bov's is not that they are all crap, not at all, the deal is that they don't have the quality control and machining tolerances some of the name brand bov's do. Because of this the first thing to do when you get a ebay style bov is disassemble it and inspect it. Look for little burrs and rough edges, look at the shaft and feel if it is smooth. It may need to be polished, and it may need to be lubricated. (not like :greddy:, I know what you are thinking :biglaugh
I just did this with my ebay Tial 50mm copy tonight, it would not open at all, but after I opened it I found that the o-ring had just stuck to the valve body because it has very high spring pressure and had probably been sitting for a while. I used some light oil on the shaft and polished it with emery cloth, now it works like a champ! Bov's are so simple inside, if you have not opened one you might want to check one out, and you will see why a ebay bov can work just as well as a name brand bov. :icon_wink
The bov has a vacuum line to the manifold. When the engine is under boost the vacuum line to the bov is under pressure, and that pressure is equal to the pressure in the intercooler pipes, so it will not open under boost. The pressure at that point is the same on both sides of the diaphragm in the bov, so it does not open. The spring tension is helping keep it closed.
Now when you let off the gas, the intercooler piping is still under pressure, but the manifold now quickly changes to vacuum after the throttle plate is closed, and this vacuum goes to the bov. The vacuum is now trying to pull the bov open, PLUS the boost pressure is now trying to push it open too, and that makes it open until the pressure is released and then the spring pushes the bov piston closed again.
Make sense? Now I explained that because I'm trying to show you that vacuum alone will not be able to open the bov, because in order to overcome the spring pressure you need boost pushing the valve open too. If you were holding the bov it would be easier to push open by hand when vacuum was applied, but you would need to push on the piston in order for it to open.
Now the deal with ebay bov's is not that they are all crap, not at all, the deal is that they don't have the quality control and machining tolerances some of the name brand bov's do. Because of this the first thing to do when you get a ebay style bov is disassemble it and inspect it. Look for little burrs and rough edges, look at the shaft and feel if it is smooth. It may need to be polished, and it may need to be lubricated. (not like :greddy:, I know what you are thinking :biglaugh
I just did this with my ebay Tial 50mm copy tonight, it would not open at all, but after I opened it I found that the o-ring had just stuck to the valve body because it has very high spring pressure and had probably been sitting for a while. I used some light oil on the shaft and polished it with emery cloth, now it works like a champ! Bov's are so simple inside, if you have not opened one you might want to check one out, and you will see why a ebay bov can work just as well as a name brand bov. :icon_wink
But to answer your actual question of possibilities why it is not opening:
1)You may not have a good vacuum line going to bov, the vacuum line may have a leak. Pull it off the bov and check it has good vacuum.
2)You may have the spring in the bov adjusted too tightly, back it off.
3)The diaphragm in the bov may have a hole or tear in it, disassemble and inspect it closely.
4)The piston may be sticking in the bore or something else may be mechanically wrong with it, causing it to stick closed.
5)The vacuum line is possibly too small diameter, try a larger size. (probably not the case with the one you have, it has an vacuum port the size of a coffee stirrer straw)
6)You may have an NA Suprabiglaugh: I hope that is not the case, but it has happened before!) Look for a big snail looking thing on the exhaust side of the engine.
1)You may not have a good vacuum line going to bov, the vacuum line may have a leak. Pull it off the bov and check it has good vacuum.
2)You may have the spring in the bov adjusted too tightly, back it off.
3)The diaphragm in the bov may have a hole or tear in it, disassemble and inspect it closely.
4)The piston may be sticking in the bore or something else may be mechanically wrong with it, causing it to stick closed.
5)The vacuum line is possibly too small diameter, try a larger size. (probably not the case with the one you have, it has an vacuum port the size of a coffee stirrer straw)
6)You may have an NA Supra
biglaugh: I hope that is not the case, but it has happened before!) Look for a big snail looking thing on the exhaust side of the engine.