Intermittent boost leak: passing BOV?
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Intermittent boost leak: passing BOV?
When boosting under the primary only I almost always get a significant boost leak (constant and loud whooshing noise). Sometimes it's not there.
A little bit after the secondary kicks in, the leak stops and I get full glorious boost.
I think the most likely culprit is bad vacuum to the BOV. Unfortunately the car will be off the road for a while because I need to do a government inspection (lame).
Thoughts?
A little bit after the secondary kicks in, the leak stops and I get full glorious boost.
I think the most likely culprit is bad vacuum to the BOV. Unfortunately the car will be off the road for a while because I need to do a government inspection (lame).
Thoughts?
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I know exactly what your talking about the loud constant "whooshing" sound and no power at all? I had the same problem, turned out it was an air pipe left loose when a body shop did some work on my vehicle, and I was the one who found out what the problem was and who fixed it too because they could't figure it out
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If the system is not pressurizing properly, the BOV's will not shut because the internal pressure is too low. That is why it only closes when you get on it because the engine is under a higher load which in turn increases internal pressure. So his reference of a loose air pipe can apply to any instance in which you may have a vacuum leak present.
Do you have a boost gauge, what is your vacuum?
Do you have a boost gauge, what is your vacuum?
#5
Check the rubber lines going from the turbo / Y pipe to the BOV things. Over time, those hoses get hard and split open. Also check your intercooler couplings. The FAQ thread stickied in this forum has a link to a site with all the troubleshooting procedures you could ever need for the stock turbos. Go there and read up on it.
#7
If you are getting full boost on secondary, then your BOV is most likely just fine. I would take a look at the Charge Control system and verify it's working properly. If it's sticking and not closing all the way, it will allow some of your primary boost to vent off during the first part of the boost pattern.
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what I mean by air pipe, is the upper intercooler piping. It was left loose during some work they had done, and I reconneted it, and the whooshing sound was gone, and there was full power once again. If I were you I would check and make sure all of your Intake hoses are connected properly to the air box, and intercooler piping etc. This is the simplest way to start diagnosing since it doesnt requre removing anything to "check" these air hoses.
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Update:
At idle i have 19.7 in/Hg of vacuum (good)
Boost pattern (according to PFC): 3.3-2.3-4.3 psi (This is not good)
I'm a little skeptical about the PFC boost reading; the car feels so damn fast! How can boost be so low!?!
Anyway, if that boost pattern is correct I think that rules out the Charge Control. Must have a leak Y-pipe forward... ?
At idle i have 19.7 in/Hg of vacuum (good)
Boost pattern (according to PFC): 3.3-2.3-4.3 psi (This is not good)
I'm a little skeptical about the PFC boost reading; the car feels so damn fast! How can boost be so low!?!
Anyway, if that boost pattern is correct I think that rules out the Charge Control. Must have a leak Y-pipe forward... ?
Last edited by koolmoe; 09-23-08 at 03:23 PM.
#10
I would get a cheap boost gauge just to verify the numbers you are seeing to start with... Also, is the car mostly stock? If so, having your boost low across the whole pattern could mean you have too much restriction in your exhaust (i.e. maybe a clogged catalytic converter).
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Mods are: JDM dp, greddy Titanium exhaust (catback), Apex-i Intakes, partially if not fully hollow cat (happened 'naturally'... pieces of cat flying out the exhaust), Power FC.
I will definitely get another boost gauge to verify, though I don't need another set of ears to verify that there is a large boost leak.
I will definitely get another boost gauge to verify, though I don't need another set of ears to verify that there is a large boost leak.
#12
There are many pieces which are venting during the boost pattern. Simply hearing a "whooshing" sound doesn't always denote a boost leak. The CRV for instance vents until around 4200 rpms. If that is not silenced (i.e. it was vented into the stock airbox but you have an aftermarket intake) then you'll hear that whooshing until it closes.
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hmmmm, well the whooshing noise existed before I installed the intakes.
The whooshing certainly sounds diminished after 4200 (when the secondary kicks in), but it's still there all the way up to redline (just not as loud).
The whooshing certainly sounds diminished after 4200 (when the secondary kicks in), but it's still there all the way up to redline (just not as loud).
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