changed bov, now 25+psi boost

[abillabong2002]

Here's the deal. My car was running at 12psi. I got a Greddy Type RS BOV. Installed the bad boy. After installing the BOV, my boost went all the way up to 25+ psi. I knew this was a big problem, and stopped boosting. I put the stock BOV back on, and it went back to 12psi of boost. I have a 98 GST, 2 3/4 downpipe(no cat), greddy evo2 exhaust, A-Pillar with boost, oil press, and a/f ratio, and a metal headgasket. Hope this info can help. Please help out a fellow DSMer!!!

 

[EclipseTrbo420A]

When you say went to 25, Im assuming you meant hit and held there. If your on the t-25 thats not possible.

The stock BOV leaks at 10 psi or around there I think. The Greddy will not leak at anything under 23 I think it was rated at. Im guess since the Greddy isnt leaking your just getting really bad boost spike as I, and many other dsmers have had with the T-25. It will Spike to 25 then fall off back to 12 Psi or what ever your MBC is set at, Just like before.

So why dont you try easing in to the throttle and controling boost till your at 12 then lay in to it alittle more till your holding 12 PSI at WOT that should proove everything is ok.
If you see the car hitting and holding at anything above 16 you have a freak of a t-25

 

[blcknspo0ln]

that's very weird that a BOV will cause your boost to go up. Im going to assume that you have your BOV/MBC lines hooked up correctly?

Could you fill us in with exactly what you touched during your install/reinstall

 

[PieEyedPiper]

Its not weird his boost went up with a bov if his original is leaking all that extra boost. My guess is he has his mbc set up wrong and or set incorrectly and his RS bov is showing the damages whereas his 2gbov is leaking anything past 12psi.

 

[abillabong2002]

When i see the boost going up that high, i lay off the throttle because i don't want to damage anything; so i don't know if it is just spiking, then coming back to normal boost. By saying MBC, i'm guessing you mean a Manual Boost Controller??? I don't have a Manual Boost Controller.
The only thing i touched when i put on the BOV was the recirculation line to the intake, and the vacuum line that goes back to the intake manifold.
I will try and see if the boost spikes up that high and drops back down. The car is also making a really whining noise, like the turbo is spinning up incredibly fast(don't know if it's the new BOV or what, but only noticed when the greddy bov installed.) What setting(hard to soft, should i set the BOV to)....Anyways, thanks for the help and questioning. I will keep you guys posted.!!!

 

[abillabong2002]

went out to eat tonight, on the way there I got on it in 2nd. Car went up to 20 psi, spun the tires, went up to 25 psi, then down to 18, then back up to 25. I have no idea what the heck is going on with this thing. It's pissin me off though. Think i'm going to just put the stock BOV back on until i, or someone else, figures this thing out <-----SAD!

 

[S_Ranger]

Sounds like a bad MBC. Ebay perhaps? Mine did the same thing, it would spike to 22-24 and then slowly go down to 18. Take it off and run the lines back to the BCS.

 

[chico904]

He said he doesn't have a mbc. I'd check the vacuum line going to the wastegate

 

[abillabong2002]

I don't see why it would be a vacuum line to the wastegate, because with the stock BOV it is perfectly fine....unless the stock BOV can bleed off that much psi??? Going to the track today(friend has a WS6 he wants to run)....I'll see if i can find something, or another DSMer that can help there. I'll keep you all posted. THANKS

 

[EclipseTrbo420A]

It is possible the stock BOV just cant sustain anything above 12 psi and is leaking all the extra boost back into your intake, but I doubt that because of the no MBC. Did you buy the car stock ? I cant see a car with those mods and an aftermarket paint job to not have a MBC ever. Maybe check to see if your actuator arm is getting stuck. Are you getting anything higher than 12 PSI on the stock BOV even a spike ?

 

[StealthXtreme4]

It is possible the stock BOV just cant sustain anything above 12 psi and is leaking all the extra boost back into your intake, but I doubt that because of the no MBC. Did you buy the car stock ? I cant see a car with those mods and an aftermarket paint job to not have a MBC ever. Maybe check to see if your actuator arm is getting stuck. Are you getting anything higher than 12 PSI on the stock BOV even a spike ?

^ Agreed. Something isn't right with that. Check to make sure there are no wastegate obstructions, that everything is working correctly, and that your vacuum lines are where they are supposed to be. ( I'm assuming this is the problem... ) You'll want to get that figured out before you keep doing pulls...

 

[BoBbOrAzE]

This was a similar problem for me back in the day when I upgraded to a 1g bov. The stock bov hits about 12psi and it all leaks back into the intake pipe, now the turbo works twice as hard to maintain the boost pressure it wants to reach but will not go above 12. With some basic mods and no mbc I put on my 1g bov. With a bov that can actually hold the pressure it climbed and spiked to 20+psi and there was a very loud whine coming from all the boost leaks on my throttle body. I solved my problem by putting on a mbc and setting it to about 13psi. Hope any of that helps you and im pretty sure it not a good idea to be even spiking to anything over 20psi with everything mostly stock.

 

[abillabong2002]

Yeah, i ordered a MBC.....the things on backorder though....i am waiting to try that out. The car is completely stock(except for what i have in my profile). Oh yeah, we got all the way to the track (hour and fifteen minutes drive), and it was cancelled due to weather. 5 degrees too cold. what a bummer....on the way there i did a couple roll ons. it would spike up there, spin the tires, and then vary from 16 to 25 just going up and down, then my cars service engine soon light came on for a couple minutes but went out later in the day on the drive home. Everything seems to be running good and fine. I put the stock bov back on, am awaiting the MBC..LATA

 

[abillabong2002]

Got my intake and MBC in today....Installed them. But its raining outside. Hopefully it will clear up tomorrow so i can try things out. Still have the stock BOV on. I'll keep ya posted

 

[MrBoxx]

Just an idea... install the MBC with the T25 compressor housing nipple as your boost source, then the outlet line to the wastegate, which is really the best way of doing it. I know a lot of people run the MBC off the BOV line because it's a manifold pressure source, but just to see if the RS BOV is the source of the problem, I would leave that line alone.

 

[abillabong2002]

Hooked up the BOV, Intake, and MBC. Everything is in perfect running order. Came to find out what the deal with the BCS was. Yeah, it's hoses were completely off of it. But its all good.

 

[abillabong2002]

It is possible the stock BOV just cant sustain anything above 12 psi and is leaking all the extra boost back into your intake, but I doubt that because of the no MBC. Did you buy the car stock ? I cant see a car with those mods and an aftermarket paint job to not have a MBC ever. Maybe check to see if your actuator arm is getting stuck. Are you getting anything higher than 12 PSI on the stock BOV even a spike ?

Yeah, me neither, considering i was the one to paint it and do everything to it!

 

[EclipseTrbo420A]

Yeah, me neither, considering i was the one to paint it and do everything to it!

well at least I asked if you bought it like that. Happy to hear you all fixed up.