Vacuum at idle after BOV install ??

[raf702]

I just installed my Sard BOV, I triple checked my vacuum routing. And prior to installation of the BOV, my boost gauge was reading 18-20hg (w/stock bpv). And now with the BOV my boost gauge is reading 15hg. What gives? Routing the vacuum lines is straight forward, which I couldnt have messed up. Does running a aftermarket BOV cause this? Or should I still be in the 18-20hg even w/a BOV? I'm stumped! help!

[Steady_One_S13]

Check the seal at the BOV pipe. It may be leaking there. My gauge reads 18-20 in.Hg. (HKS SSQ)Check your BOV. Is it used or brand new?

Double check all hoses and listen for whistling sound.

[Justin35ll]

Your sucking in more air then you were before. So you probably have a leak somewhere.

[raf702]

Thank you sir, the adapter wasn't tight enough on the BOV. Now the vacuum is reading 19-20 hg.

Now I got a couple questions since I just installed my BOV last night.

As I was looking for a vacuum source for my BOV. I noticed there was a vacuum hose running from the wastegate actuator to the manifold, which I heard is not a good thing. Since wastegates don't like vacuum? If so why?

So then I rerouted the vacuum hose from the wastegate actuator to a nipple/port on the coldside pipe of the stock smic, which I assume is correct? According to what I've read here in the forums. So then I routed a new vacuum hose from the port on the manifold and connected it to the BOV. Which I know is correct.

Now boost is reading ~7-9psi which stock should be on a T25. But before, when I had the vacuum hose running from the wastegate to the manifold. Boost was actually spiking up to ~14-15 psi, I assume this was wrong? I guess the previous owner hooked up the wastegate hose wrong.

Lastly, driving on the freeway, all of a sudden I lost boost, no power, nothing and car died!. So I got to the streets safely and I continuously had to turn the car on or blip the throttle in order to keep the car on. Some smoke would come out the exhause, and slight compressor surging. I was able to make it to the nearest Autozone. I popped the hood and the BOV came off!! LOL, the coupler had a crack which the BOV came loose. Well I got a new coupler retightened everything.

And now the car is running smooth, no surging, no smoke or anything else. Could I have damaged anything during the time the BOV came loose?? Thanks for everyones input

[Justin35ll]

Yeah 7-9 psi is stock I don't know why you were running 14 - 15 when it was connected to the manifold, cause mine is connected to the manifold now and I run 7 - 9 and it is tee'd off the BOV too.

You probably didn't damaged anything, but the car would have def run like s*** with the problem you had. As long as it's running smooth now

[raf702]

Yeah 7-9 psi is stock I don't know why you were running 14 - 15 when it was connected to the manifold, cause mine is connected to the manifold now and I run 7 - 9 and it is tee'd off the BOV too.

You probably didn't damaged anything, but the car would have def run like s*** with the problem you had. As long as it's running smooth now

That's pretty strange, cause I read on a previous thread, someone had the same accidental setup, and was boosting up up ~14psi when he had the wastegate hose connected to the manifold.

Both my bov and wastegate have their own dedicated lines, so there's nothing T'd into them.

Also if I was to add an MBC, I know one port goes to a vacuum source, which I can "T" into the same line as my boost gauge. And the other port I can "T" into the hose of the wastegate actuator. Does that sound correct? Thanks again

[raf702]

A quick diagram I drew for an an MBC installation: Let me know if this is correct?



For the vacuum source, I plan to "T" into the hose from my boost gauge. Correct?, Thanks for inputs

[snake240]

http://jimwolftechnology.com/w...S.PDF

[snake240]

for the gauge, T in between the fpr and top left nipple on throttle body.

[raf702]

for the gauge, T in between the fpr and top left nipple on throttle body.

Well my boost gauge already has a vacuum source. I was planning to "T" the current vacuum hose from boost gauge with the mbc.