BOV Leak Of Some Type

[Vermont]

My mods list is included in my jornal for all wondering but I do NOT have a VTA BOV. I have the stock valve still on the car. I noticed a problem with it a few weeks ago. I did not know what it was at first and just thought it might be my poorly scaled MAF. What is happening is that every time I shift gears or let go of the throttle I am seeing a very quick rich spike on my AEM UEGO, it then goes slighly lean and then back to normal, all in a matter of seconds at most. The richness is progressive with the amount of boost. So at partial throttle and 5-10 mmHG I will only see a spike from 13.7 down to 1.8 or so. The more boost that is applied the richer it goes. I have not checked out the valve yet as I finnally figured out what was going on while driving to school and am now sitting in class. I will be taking a look at it later this afternoon. I do not belive that I should need a need BOV as I am only running 21psi on the stock turbo and from what I have read that should not be causing any problems

What I was wondering is, what should I look for in identifing the location of the leek? Could it be a blown gasket on the BOV causing the issue? I do know that the nipple on the turbo is still connected as this is what my boost gauge is tapped into. Maybe a crack or split in the recirc hose? Or maybe I put to much boost through the valve and it is now blown?

Any ideas and or personal experiance would be helpfull at this point.

 

[Z1107]

Thought the stock BPV was only rated for 20lbs of boost?

 

[HolyCrapItsFast]

If there was a crack or tear in the return hose this would constitute a leak after the maf and before the trubo... your fuel trims would be off the charts accross the board at that point.

Again if it was a bad gasket it would go rich while under boost and lean at idle and not just as you shift... Not to certian what to say in this case.

 

[HolyCrapItsFast]

Like I said. Safe bet is to pull it and all connection pieces. Crush the BOV and reinstall making sure everything seals.

Stock BPV may only be rated at 20psi, but mine held 25 psi like a champ and I didnt have any issues until 30 psi. And in that case I actually had a pinhole boost leak on the vaccum hose going to my boost gauge. Crushing a BOV is an evo community technique to get the stock BOV to hold more boost.

What is "crushing" a BOV... I'm not being a douche, I really don't know :lol:

 

[Vermont]

If there was a crack or tear in the return hose this would constitute a leak after the maf and before the trubo... your fuel trims would be off the charts accross the board at that point.

Again if it was a bad gasket it would go rich while under boost and lean at idle and not just as you shift... Not to certian what to say in this case.

I checked my learned fuel trims this morning in Learning view (had to clear a code). Only the last D value was above 5.00 (was at 9.60). I think it might be a bad gasket as it does go pig rich under full and partial boost, along with it idling up at 14.7 (should be at 13.7 due to lack of a rear O2 sensor).

Like I said. Safe bet is to pull it and all connection pieces. Crush the BOV and reinstall making sure everything seals.

Stock BPV may only be rated at 20psi, but mine held 25 psi like a champ and I didnt have any issues until 30 psi. And in that case I actually had a pinhole boost leak on the vaccum hose going to my boost gauge. Crushing a BOV is an evo community technique to get the stock BOV to hold more boost.

Do you happen to have a link or write up on how to crush the stock BOV? I am going to replace the gasket and see if it fixes the problem but I might need to crush it later on.

For all concered as well I am getting the loud PSSSHHH sound of a VTA BOV. It is lound enough for me to hear it inside the car.

 

[Vermont]

I am going to swing by a dealership on my way home in a little bit and pick up a new bov gasket. I will also check the hose leading back to the intake tract. I don't have any carb cleaner to check for leaks that way so it will all have to be by hand.

 

[Td_d]

I checked my learned fuel trims this morning in Learning view (had to clear a code). Only the last D value was above 5.00 (was at 9.60). I think it might be a bad gasket as it does go pig rich under full and partial boost, along with it idling up at 14.7 (should be at 13.7 due to lack of a rear O2 sensor).

I've got a trick for you that will deal with this issue that the rear O2 delete causes. You'll kick yourself - use the closed loop fueling tables to add the required 1 AFR point back, and you're back at 14.7.

 

[Vermont]

I checked my learned fuel trims this morning in Learning view (had to clear a code). Only the last D value was above 5.00 (was at 9.60). I think it might be a bad gasket as it does go pig rich under full and partial boost, along with it idling up at 14.7 (should be at 13.7 due to lack of a rear O2 sensor).

I've got a trick for you that will deal with this issue that the rear O2 delete causes. You'll kick yourself - use the closed loop fueling tables to add the required 1 AFR point back, and you're back at 14.7.

So just bump it up too 15.7 you think that will work? If it does I will shit my self...

I still have to try out your SD hack on my rom, haven't had the chance with finals next week and all.

 

[Vermont]

Ok, so update time.

Replaced the BPV gasket with a brand new subaru OEM one, then did a visual inspection of the air return hose. Found no problems with the hose although the old gasket did look all chewed up, from taking it on and off a lot. The problem still persists. Still sounds like I have a VTA BOV, going rich when I shift depending on throttle input.

Any other ideas or maybe I am just crazy and it is not a problem.... I am not so sure though....

Just to clarify the BPV is making the PSSSHHH sounds when under partial to light throttle. I can't tell if it is doing it at WOT throttle and shifting due to me having a EWG. Next thing I am thinking of doing is spraying around the the area with Carb cleaner to see if the idle changes...

 

[Z1107]

Mine was doing that right before my turbo blew. When I pulled off the BPV the gasket was all chewed up. Not saying it had anything to do with the turbo. I know Fuji said the BPV can handle more than it's rated to, but I don't know if would want to risk a few grand over a couple hundred dollar part. But if you need another oem BPV let me know I got one laying around.

 

[Vermont]

Well I am replacing the stock Turbo within the next month or so as my Blouch Dom 1.5xt-r comes in next week. I was planning on going VTA and speed density as well but.... I was just going to run the stock BPV till my AWIC setup came in... I am going to pull the BPV this week end and inspect it, if I fix the celica that is.

 

[Td_d]

I checked my learned fuel trims this morning in Learning view (had to clear a code). Only the last D value was above 5.00 (was at 9.60). I think it might be a bad gasket as it does go pig rich under full and partial boost, along with it idling up at 14.7 (should be at 13.7 due to lack of a rear O2 sensor).

So just bump it up too 15.7 you think that will work? If it does I will shit my self...

I still have to try out your SD hack on my rom, haven't had the chance with finals next week and all.

Not the open loop primary table - that will not let you go above stoich - which is exactly why the closed loop fueling target compensation tables (load) are there. And they can be edited both positive and negative (negative stock). Apparently the ecu starts not liking you much if you bump it up more than 0.5 to 0.6 AFR - but even that would make a significant improvement to 13.7.

I still haven't had the time to test out the SD hack either, so bleeding swamped at work. I think my O2 sensor might be taking a shit on me as well, I've started having some weird closed loop driveability issues recently, so want to sort that out, and then hopefully start tuning in SD.

 

[Vermont]

Not the open loop primary table - that will not let you go above stoich - which is exactly why the closed loop fueling target compensation tables (load) are there. And they can be edited both positive and negative (negative stock). Apparently the ecu starts not liking you much if you bump it up more than 0.5 to 0.6 AFR - but even that would make a significant improvement to 13.7.

I still haven't had the time to test out the SD hack either, so bleeding swamped at work. I think my O2 sensor might be taking a shit on me as well, I've started having some weird closed loop driveability issues recently, so want to sort that out, and then hopefully start tuning in SD.

Ok sweet I will given that a test out and see how it works.

As for the SD, I still need to do a lot of reading, hell even find some good SD tuning sources. Because as of right now All I know about SD tuning is that the Volumetric Efficiency table is very important and takes time to nail down right.

 

[ZachTTLM]

do a snoop test...this is a back yard way to check for leak...just like you would for a leak in a tire. Mix up a soapy/water solution in a spray bottle. Start the car and mist it on each part at a time small sections at a time burp your throttle a little bit to see it if bubbles. May help you find a leak or bad seal.

 

[Bluedemon_II]

I have never been a big fan of crushing the bpv. If you get to the point where you need to do that, go buy an aftermarket adjustable unit. Did you check the bpv return hose to see if it is a little lose?

 

[ZachTTLM]

I agree with Bluedemon, buy aftermarket before crushing the bpv

 

[Vermont]

I completely agree with you guys... If you comes down to the BPV being toast them I will just pick up a new bov.

I am hoping though that I did fix the problem. I was checking out the car Saturday when I noticed that the intake looked kinda funny..... Well as it turns out my intake filter had fallen off.... No idea how that happened, but I reattached and I hope that might solve the issue.

 

[Bluedemon_II]

I completely agree with you guys... If you comes down to the BPV being toast them I will just pick up a new bov.

I am hoping though that I did fix the problem. I was checking out the car Saturday when I noticed that the intake looked kinda funny..... Well as it turns out my intake filter had fallen off.... No idea how that happened, but I reattached and I hope that might solve the issue.

If the filter was off, you will hear the sound of the bpv actuating. Go drive the car again and see if it keeps doing the sounds.

 

[Vermont]

The super loud sound did stop. My AFR's under boost are also back like they should be. Only problem is that it is still going pig rich for a split second on shifts. I do not think it is normal as I have never noticed it before. Any idea on what might be causing that? I am going take it out for a decent log this weekend to try and figure it out. I was going to log some of fuel related variables. Although Last time I looked at a learning view my learned trims were all good with only the D value being over 5.00, which makes me think it is not a fuel problem.