I have an 88 vert with a jdm t2 s5 swap. Motor is mild street ported. Rc 550 primary and 750 secondary's, racing beat rev ll 3" downpipe back exhaust, rtek 1.7 modded ecu.
Ok so this is my issue. I bought this car and it wasn't finished, so no it's starting and driving fine but needs a BOV cause the original owner didn't have one on there... The problem I'm having is when I try to hook up the vacuum line from the BOV to the intake the car won't idle. It just bogs and barley idles at like 500 rpm. It's atmospheric Pettit racing BOV. What I need to know it what is the exact way to run the vacuum line for the BOV. And where on the intake to hook it to. I've tried a few ways and it either makes the BOV not work or kill the cars idle. Or turns the car off.

 

You can use the line that goes to the air bypass valve. (green) - Or you may tee in the BOV vacuum line with the line coming from the pressure sensor. (yellow)

Or you can remove the BOV altogether.

Okay, so the diagram I am trying to post keeps going away.

Here is a link to the vacuum diagram. -> https://www.rx7club.com/2nd-generati...ne-bov-983739/

 

This is the problem I'm having. The car was prolly never vacuumed right in the first place. That's why I need a layout of where everything would go. And why would I remove the BOV and create damage to my turbo? It creates turbo chatter and will kill my bearings in no time plus it runs hotter without a BOV cause of there being no place for the built up pressure to go but back through the turbo. Bad idea

 

Lots of people run without BOV's... It's just another fail-point.

 

And also there is no BAC or air control valve on my throttle body

 

The "rats nest" is also removed. I tried what that link says by hooking the BOV to one of the nipples and... The top nipple made the car turn off but while revving BOV worked. The middle nipple it ran fine but BOV didn't work. And I didn't try the bottom one cause I gave up.

 

If the car runs without the BOV being functional but doesn't run while the BOV is functional... Then it sounds like the issue is the BOV. Is the BOV adjustable? You're sure doesn't need to be recirculated??

 

The BOV is brand new... And if I was to recirculate where would I recirculate it to? There is no air box in my car.

 

And no not adjustable.

 

You'd want to recirculate it to a large nipple on your TID. (Turbo inlet duct.)

 

the bottom is vacuum which is where the bov should be connected to.

 

Ok I guess I gave up too easy... And it started raining, I gots no garage but I'll hook it up atmospheric and post back. Thanx

 

Now is it ok to have the pressure sensor and BOV hooked to the bottom nipple on the throttle body? Or just the BOV and route the pressure sensor elseware?

 

i run the FPR and pressure sensors on their own separate vacuum sources but either way will probably work.

 

Ok good to know. I'd rather have it all on separate vacuums anyway. This way there's no T's and vacuum loss. Not to mention less vacuum plugs

 

Ok so I tried the bottom nipple and it did the same thing as the top nipple. Do I tried the only other one on the UIM which was the top nipple on the back close to firewall and nothing changed. I don't get it. I've tried tapping into the pressure sensor, boost gauge, and every nipple on the UIM. I'm lost unless this BOV is just simply no good.

 

are you still running a maf? maybe that bov is running open under vacuum and causing the air metering to be off

-sean

 

Yea still runnin the t2 maf

 

Brings this back into mind. ^

 

What bov are you using? Might have issues if it's a Freddy, Greedy or an Apex'e.

 

^

 

I'm not sure what's happening... I think I'm just gonna ditch the idea of that BOV til I put the FMIC and hks BOV on...

 

Does anyone have a vacuum diagram based off a eliminated BAC and ACV and "rats nest" for a jdm s5 turbo 2??? This would be very helpful

 

I could be wrong, but I'm not sure anyone has made anything like that. Why not use the diagram in the link I posted? I don't have any emissions and I'm still able to utilize it. You just need to picture in your head what you have to work with and compare it to the vacuum diagram in the link. I mean, it still proves to be useful.

 

True I guess I wasn't using my head lol. But I just figured if anyone has a diagram then that would save me some headaches. Cause I've tried all I could think of but nothing seems to be working out... So if anyone has one then I at least would know the right way and work out the bugs from there