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Billcriss
05-07-2017, 07:29 AM
I have the CXracing intercooler kit with there BoV. The car runs fine but at idle it acts like it has a HUGE Cam. To the point where it damn near shuts off. But when I rev it, it's fine. Any idea?


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Juantwo3
05-07-2017, 08:45 AM
How is you iacv set up, are you using a greddy intake manifold or oem one
Billcriss
05-07-2017, 08:53 AM
How is you iacv set up, are you using a greddy intake manifold or oem one



Im using the OEM one. https://uploads.tapatalk-cdn.com/20170507/c93df89adb49e7955ff1bfad731f9715.jpeg

#9 is going to my boost gauge
#8 is capped off
#7 and #6 is going to my BOV



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Billcriss
05-07-2017, 09:11 PM
anyone got any ideas?


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feito
05-07-2017, 09:33 PM
Im assuming your bov is recirculated
sblack13
05-07-2017, 10:47 PM
Shouldn't #8 Goto brake booster?
djdryon
05-08-2017, 02:07 AM
A recirculated bov helps a lot with stabilizing the idle. Also, why do you have two hoses going to a bov?

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Billcriss
05-08-2017, 04:48 AM
A recirculated bov helps a lot with stabilizing the idle. Also, why do you have two hoses going to a bov?

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Honestly I have no idea. The OEM one had 2 so I assumed that's what I needed to do. The BOV does have two nipples though...


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Billcriss
05-08-2017, 04:49 AM
Shouldn't #8 Goto brake booster?



I don't have a brake boost. I have the boost delete from chase bays


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djdryon
05-08-2017, 05:16 AM
Honestly I have no idea. The OEM one had 2 so I assumed that's what I needed to do. The BOV does have two nipples though...


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Interesting. Never seen a bov with 2 hoses. I don't see why you couldn't just use one hose with a splitter...

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Billcriss
05-08-2017, 05:21 AM
Interesting. Never used a dual port bov. I don't see why you couldn't just use one hose with a splitter...

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https://uploads.tapatalk-cdn.com/20170508/277828fe772e1ad0525f6a84cb131b15.jpg no idea if this is right but this is how I assumed it should be. Could very well be wrong



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djdryon
05-08-2017, 05:45 AM
That's a strange design. Both hoses applying equal pressure/vacuum to each side of the piston/diaphragm would totally negate each other... I know that design is used for wastegates, but each side gets air from a different source.
By design the top port goes to the intake, so the valve is held shut under boost and pulled open under vacuum (when the throttle plate is closed) I can only imagine the bottom one would go to an opposing force, so pulling under boost and pushing under vacuum... but how this would be plumbed in...


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RB25GUY
05-08-2017, 05:48 AM
bottom line needs to be open on the BOV. A tune might help aswell.
Billcriss
05-08-2017, 05:53 AM
bottom line needs to be open on the BOV. A tune might help aswell.



So cap one of the nipples on the intake and leave the bottom nipple on the BOV open? The goal is to get a power FC in a few weeks to and a few more goodies. But I need this to start acting like it should lol


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djdryon
05-08-2017, 06:05 AM
So cap one of the nipples on the intake and leave the bottom nipple on the BOV open? The goal is to get a power FC in a few weeks to and a few more goodies. But I need this to start acting like it should lol


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Yes, try that. If the bov is staying open at idle, you'll have a vacuum leak, which will cause a rough idle.

Did some reading and if yours is a dual spring bov (and you are recirculating), I guess you can have them both from the intake, but make sure they're connected to the SAME source, so there's no pressure differentiation.

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feito
05-08-2017, 07:50 AM
Next time dont assume and do more research. That vta freddy bov wont give you a vac leak, but it will leak air out at idle. This is a very old and well discussed topic, you should have done more research on it.
Just recirculate that bov and leave the bottom nipple Disconnected
Billcriss
05-08-2017, 05:57 PM
Next time dont assume and do more research. That vta freddy bov wont give you a vac leak, but it will leak air out at idle. This is a very old and well discussed topic, you should have done more research on it.
Just recirculate that bov and leave the bottom nipple Disconnected



Should I cap 7 or 6?


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dwnshft2drft
05-08-2017, 06:26 PM
Download FSM and BOV manual just to double check stuff. Cleaning IACV and throttle body would help idle.
djdryon
05-08-2017, 07:05 PM
recirculate that bov and leave the bottom nipple Disconnected
What he said [emoji115]


cap 6 or 7?

I'd cap the lower one, since it'll give you a cleaner-looking install. Best way ive found is a nipple cap with a hose clamp. Been holding fine on my KA-T for years with 15psi. Do the same with the one you stuck a bolt in.

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Billcriss
05-09-2017, 05:47 PM
Seems to be running great!


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