leak, possible BPV problem??

[jmv]

Alright so a little background on my issue...

the car had been having problems with bucking during part throttle, once the throttle opening got high enough to get into boost (yet no problems at WOT). It seemed like occasionally it would act as though there was a vacuum leak... i know that doesn't make alot of sense, but sometimes it wouldn't be running real well and the gauge would read about one less in/Hg than normal at idle. Other times it read as normal.

Today i started getting compressor surge, which i haven't had since i got my new intercooler (included larger (1" I.D.) fittings on the pipe, and a boost sciences reflex diverter valve). I couldn't mess with it right then since i had to go teach, but when i was done i checked it out and i'm still getting the compressor surge like i would get when i had the stock BPV and an AEM intake. There is definitely a vacuum leak, now i am reading about 3 less in/Hg than normal at idle, the idle is rough and sporadic, and if i put in the clutch after accelerating, the car will die. I have to let off the gas in gear and then let out the clutch to keep it from stalling.

I've got silicone vac lines for all the small vac lines (3/16" maybe??) and have just checked my wastegate actuator 3 days ago and its not bad. Is it possible that the upgraded bypass valve has gone bad?? I don't know where to start looking for this issue.

 

[axisboldaslove]

somebody find him an answer....!!

 

[mikeski]

it could be that the bpv is leaking.

 

[jmv]

... how can you tell??

 

[mikeski]

do u have the stock bpv? if so exchange them and see if the problem still exists.

 

[jmv]

i've got the stock bypass valve at my parents house, but i'm not sure it will be easy to hook up because of the different size hose... i'm not sure how to transition down to the smaller inlets for the stocker.

But i did read on the boostsciences website that they have a lifetime warranty on their products (although, i didn't buy it directly from them so that could complicate things), and their mailing address is local so maybe i could have them take a look at it for me.

 

[axisboldaslove]

yeah i would say that they probably couldn't warranty yours...cuz you bought it second hand...but that is what i would do is have them look at it ...or i dunno have somebody who knows alot about cars take a look

 

[mikeski]

take pics and post em, we can diagnose better! did u check all the hoses?

 

[jmv]

I re-checked the vac line running to the BPV, and it was actually leaking (it wasn't 3 days ago when i had checked it)... i pulled it off and the end had torn by the hose clamp. So i fixed that, turned it on and it seemed better, but once i revved it enough for the BPV to work it started running like s*** again.

i took the BPV off, and took it apart.... it was super gunky/dirty. I cleaned up the gunk and checked the seals, the o-rings (all 3) looked fine, so i'm going to run to the autoparts store and grab some grease, re-grease it and see if that makes a difference.

It was a b**** getting those hoses off though, since they live right next to the radiator and theres like zero room to work down in that corner.

 

[jmv]

can anyone tell me, if there was a leak in the system somewhere besides the BPV, if that would be a cause of compressor surge??

For the life of me i can't find a leak.

I reassembled the BPV and its still getting compressor surge and acting as though it had a leak. The BPV was a very snug fit when i reassembled it, and i'm curious if maybe the cylinder in there isn't moving freely enough when it needs to.

If anyone could help me shed some light on this, that would be spectacular, i'm not sure where else to look for problems.

 

[mikeski]

do u have a boost gauge? you can tell if there is a leak, maybe its just louder turkey sound because of the new bpv. does it idle funny?

 

[jmv]

yes, i have a boost gauge. It reads as though there is a leak, i'm getting ~1-2 less in/Hg than usual (my gauge has always read low vacuum, so that means 17 or 18 instead of 19). Its not a turkey sound either, my car has never had the turkey even when i had the AEM intake and stock BPV. Previously it was just a solid whoosh, now its the same type of whoosh sound, but with distinct cycles in the sound which to me indicate compressor surge (its the same sound i had when using the cheap stock BPV that didn't flow enough air). The BPV i'm using isn't new either, i've run it for 2 years with basically the exact same setup with never a hint of compressor surge, and all of a sudden i've got the car reading that it has a leak, getting compressor surge, and idling like s***.

 

[mikeski]

hmmm, maybe the wastgate? how much is your boost reading?

 

[jmv]

the boost reads 7 psi, no spikes, and blowing into the wga line reveals no leaks.

 

[jmv]

car has started to throw a CEL, code P0171, bank 1 too lean.

I can hear the compressor surge when letting off from acceleration, even when the acceleration is slight enough to only get 10 in/Hg on the boost gauge. Its like the bpv isn't functioning at all.

I really need some help with this, i have to travel 40 miles to work and don't feel comfortable doing that in a car that isn't working right or might leave me stranded....

 

[HP10T]

You need to find someone with a leak tamer or possibly make your own if you have access to an air compressor.
Blowing into the hoses isn't going to show you anything since you need to pressurize your system to 7psi or more.

 

[jmv]

You need to find someone with a leak tamer or possibly make your own if you have access to an air compressor.
Blowing into the hoses isn't going to show you anything since you need to pressurize your system to 7psi or more.

well, for whatever its worth, the diaphragm on my wastegate actuator has gone bad before and i've checked it by blowing into it, and it was a completely suitable test... however the problems i'm having don't really suggest that problem anyway since i'm not having peak boost issues of any kind.


Anyway, i've discovered that it takes slightly more vacuum for the boostsciences valve to open than the stocker.... the stock one will begin to open with about 6 in/Hg applied to it, whereas the boostsciences valve won't open till about 11 in/Hg. However both are definitely fully open by the time you get to 17 or greater in/Hg. Does a bpv stay open at idle?? I was under the impression that they remain closed until the throttle is closed and they have to relieve that pressure, but perhaps i'm misunderstanding the exact mechanics of it. Since both of the valves sitting in front of me are fully open at 11 in/Hg or greater, i can only assume that they sit open at idle. If thats the case, then i don't really see how the bpv could be causing my problems, which means i have no idea where to look now....

 

[cmahlig]

looks to me like its the valve dude. when you go home put the stocker on and just clamp the s*** out of it and see what happens. the stock is 3/4" so you should still be able to clamp it good. ill be in san marcos at like 4 so if you are still there, ill look at it really quick.

 

[kachur779]

wouldnt the 1 inch hoes fit over the stock bpv hoes ?

 

[jmv]

i'll try to get the stocker on there later today.... i think i'm also gonna try and check that the vac reading i'm getting from the gauge is getting all the way to the end of the line for the BPV.