Worn Out Stock B.O.V.?

[Brady]

So, I dont know if any of you guys saw my last post on my lack of acceleration and by lack i mean almost non existant

My first concern was a vacuum or boost leak but I got it smoke tested at a reputable garage and they said the problem could be from a worn stock BOV?

Can someone let me know how that would work and whether to buy the copy HKS SSQBOV from driftmotion?

kthx

 

[GrimJack]

Pull off your stock unit and attempt to blow through it. If you can, it's pooched. This is actually fairly common - however, this doesn't usually create THAT big of an effect, makes your turbo spool a little slower is all.

If it's toast, you'll need a replacement - either a bosch style unit (cheap, works) or one of the higher quality BOVs from HKS, Greedy, whatever.

 

[MA717MGTE]

nice tip Grim! thx

 

[Brady]

well if its not working at all what would the symptoms be?

how can the BOV failing take away so much power?

 

[peteyturbo]

It will cause a severe boost leak, which makes a big loss in power, and an overworked turbo..I would test it with VACUM not SMOKE..Just take it out and see if it seals..

 

[jetjock]

how can the BOV failing take away so much power?

As Grim Jack said it shouldn't. Your problem likely lies elsewhere.

 

[Brady]

what about what petey said?

 

[jetjock]

Well, it's simple: Like many on this forum petey doesn't know what he's talking about. It's just another reason you should read the TSRM and learn about the car yourself. That way you'd know for sure instead of having to ask a bunch of yahoos on the internet and then wonder who to believe.

 

[Brady]

touche,

well how bout you jetjock you seem to be a self proclaimed resident expert, pretend you were my mechanic, whast the first thing u would look for?

 

[GrimJack]

Well, Petey is kindof right. It does create a boost leak, however, it's not usually a big enough one that your turbo can't push enough air to overcome it. You'll definitely be overspinning your turbo, but I've seen lots of Supras live through this without any real problems.

I'd test the intake with pressure, not vacuum or smoke. I'd use the system detailed here: http://www.supramania.com/forums/showthread.php?t=19718&highlight=boost+leak+tester

 

[GrimJack]

Good point, JJ. I need to stop listening to what people guess it is and check the obvious things.

Looking at this from the very beginning... I'm not sure I'd even want to try to pin this problem on a boost leak in the first place.

The first thing I would do is check for engine error codes. I'd check the throttle linkage, plugs, coils, and wires, and make sure my exhaust wasn't plugged (at the cat. converter) or crushed (by a speed bump). I'd run a boost leak check. I'd pull off the oil cap with the engine running to check for excessive blowby - signalling one or more broken pistons, badly fried rings, or something else wrong with the combustion chamber seal. I'd probably check for a BHG using a block tester. I'd check the fuel delivery. I'd pull off the 3000 pipe and stare into the throttle body while mucking with the gas pedal, make sure it's still opening all the way.

 

[jetjock]

Diplomat Dave

Boost leak? Ok, in a sense. Severe? Nope. Big loss of power? Nyet. You could drive around with bad stock valve for months and never know it. In fact that's usually what happens to people. I just went over a car the owner claimed was running great. Guess what? And I don't remember how long I drove around with mine busted until I stumbled on it. As you said it has little impact.

Brady: Not self proclaimed. I may be a resident expert but I didn't ask for this job you know. And I'm not your mechanic. Doesn't pay enough

 

[peteyturbo]

You may have a high post count sir, but you surely do not come across to me as very bright on this subject based on those last two posts..First, please tell me what I said that would lead you to believe that " I don't know what I am talking about"..
Then please explain to me how an open BOV will not effect power output, it is essentially a recirculated boost leak..

Don't worry, you will never catch me referring to you as a resident expert and I think its funny that anyone would after what I have just read..

Diplomat Dave

Boost leak? Ok, in a sense. Severe? Nope. Big loss of power? Nyet. You could drive around with bad stock valve for months and never know it. In fact that's usually what happens to people. I just went over a car the owner claimed was running great. Guess what? And I don't remember how long I drove around with mine busted until I stumbled on it. As you said it has little impact.

Bardy: Not self proclaimed. I may be a resident expert but I didn't ask for this job you know. And I'm not your mechanic. Doesn't pay enough

 

[peteyturbo]

You can also test them with vacum to check valve function, right on the vacum nipple..Should be an opening pressure criteria in the fsm..

Well, Petey is kindof right. It does create a boost leak, however, it's not usually a big enough one that your turbo can't push enough air to overcome it. You'll definitely be overspinning your turbo, but I've seen lots of Supras live through this without any real problems.

I'd test the intake with pressure, not vacuum or smoke. I'd use the system detailed here: http://www.supramania.com/forums/showthread.php?t=19718&highlight=boost+leak+tester

 

[Brady]

shit man all of this is pretty daunting to me, I was hopin the smoke test i had done would do the trick, I was really looking for an easy fix

 

[peteyturbo]

Well regardless of what we are saying, it is pretty unlikely that the symptoms you are having are from a bad BOV
You really need to be alot more informative with what is going on with your car so people can understand more of what is going on in order to help you out..
PRessure test the turbo system to 20psi and look for leaks, that could be a possible easy fix..

shit man all of this is pretty daunting to me, I was hopin the smoke test i had done would do the trick, I was really looking for an easy fix

 

[MKIIITrbo89]

I have a quick question regarding BOVs, don't mean to high jack this thread or anything but it is fairly relevant.

I have a Greddy Type S BOV and it has been installed on my car for over a year. However it is hooked up with a tri-hook-up connecteter with one line going to the Greddy BOV, one going to the stock BOV, and the other goes back to the engine somewhere. This is how the directions instructed me to install it. I have not been having any problems but always wondered why you would run the Greddy in conjunction with the stock BOV. Is this common? Should the stock one be removed all together? What are the benefits disadvantages of this? Thanks for the help.

 

[starscream5000]

The stock BPV will still recirculate some of the air back into the turbo, keeping you from backfiring and stalling as much as if you were just venting all bypassed air into the atmosphere. Helps some, but the best thing to do is to recirculate all bypassed air back into the accordian tube .

 

[Brady]

ok I jus bought and and installed a HKS SSQ bov lets see if this shit makes a diff

 

[a_sesshoumaru]

check if your throttle closes properly first