No boost, low power, no CEL

[Disgust]

Ok, I made a boost leak tester per Doobs post. I decided to test all the components independently with the boost leak tester. I removed the intercooler, plugged one hole with the boost leak tester and the other with a plug. I did not feed vacuum or boost pressure into the nipple on the BPV and left this to ambient pressure. The intercooler held pressure until about 5-6psi when the BPV opened. I researched and this is normal when the nipple is left open.

 

I then connected the boost leak tester to the TB hose and pressurized the system. I heard gurgling and then a "whoosh" from the turbo cold side outlet. With all vacuum connections capped off for the turbo inlet, the only was for the turbo to make noise is if air is flowing through the exhaust, or somehow a lot of air was getting into the crank case. I then hunted down the PCV valve and removed it's boost/vacuum line connecting it to the intake manifold. When I plugged this line, I was able to hold pressure in the system. Held 10-15psi for about 8-10 seconds which seems reasonable to me.

 

Oh yeah, also my PCV valve looks like this:

http://i236.photobucket.com/albums/ff167/newpinesap/DE925458-B5CA-4D12-B349-FB36363B69F1_zpszhwk2hog.jpg

DERRRRRRRRP

Edited May 29, 2015 by Disgust

[doobaruGT]

Sounds like you've got some good problem-solving skills happening here.

[Disgust]

Sorry to be such a nuisance, but I’m feeling super defeated on this car. I am a CNC machinist (mechanical engineer) and work about 50 hours a week so I have been literally working on this thing in all of my free time that I’m not crushing brews. Oh yeah, I’ve also done all testing and repairs to this point with a broken pointer finger so it’s going much slower than normal haha. Anyways, onto the important stuff:

 

 

 

Last night I replaced the PCV valve with an OEM assembly I got from my subaru dealer. I also made sure the blue T-Valve was connected and checked all my vacuum lines. I tested the car again thinking to myself “finally I can drive a real car again” and again I have the same issues with no boost.

I am really, really wondering if this is a turbo assembly problem or if I just somehow haven’t found the vacuum leak. Because the root issue happened under full boost, I know I either g-naded a turbo or blew something vacuum/boost related.

 

So let me confirm a few things before proceeding:

1: If I blew my turbo, I would have tons of shaft play on the exhaust side.

2: If I seized my turbo, I wouldn’t have been able to spin the turbine.

3: Nothing electrical affects boost pressure until around 5psi (aka, if this was electrical and not mechanical, I would still be getting some boost pressure so therefore it must still be a mechanical issue since I have zero boost)

4: If a single vacuum/boost line has a crack or leak, I will get no boost. (if true, I’m just going to go through with 15 ft of vacuum hose and replace it all)

 

Thanks again for all that helped so far and especially doob

[doobaruGT]

I looked back part way and noticed you found a leak on your BCS. Did you confirm your BCS is working? An easy way to do this (if you don't have a spare) is to plug in your green connectors and let the car run test mode while the key is in the "on" position but not running. You can then blow in each port as it cycles. It should cycle and close/open each port.

 

I'll look for more details in the meantime.

 

 

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[doobaruGT]

The more I think about this, it has to be a decent vacuum leak.

 

You're getting boost. Just not positive numbers.

 

Your turbo moves with no shaft play (hence the increase in pressure in the line.)

 

I can't recall, did you check the blue T under the IC? Edit: saw you checked this

 

Also. I don't know much about the err on the dash, but that's suspect to me. I've seen a few of these pop up but haven't investigated the cause.

 

Lastly, what made you pressurize from the TB and not from the inlet side?

 

Maybe a professional smoke test would be worth it at this point. I've been there so I can relate to your frustration!

 

 

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Edited June 4, 2015 by doobaruGT

[doobaruGT]

One last thing. How about your wastegate? I'm wondering if it's stuck open or something. I even read of the wastegate door shearing for one member. That's obviously not common. You did say you pulled the exhaust side to check for play. Do you remember what the WG looked like?

[Disgust]

So I did check the wastegate when I was checking the turbo, but I haven't checked the BCS yet. Wastegate seemed stiff, no movement and nothing super out of the ordinary. I did research on the BCS as this is the next system to track down in my vacuum diagram, but haven't figured out a sufficient way to test it yet so thanks for the advice.

I'll test it using that method tonight or tomorrow morning and let you know.

 

I have scheduled for a professional smoke test yet it is taking a very long time to get an appointment at the shop, so I'm trying to track it down on my own before hand.

 

I'll research more about the err message too because it would pop up only while decelerating for a very long time, go away, and then was on the entire time.

[Disgust]

So I was thinking about an old 98 fozzy I had that was having some issues and I remember it was all MAF related. I think the smoke test will tell, but is there any way this could be a weird cause as I know the mpg and instant mpg sometimes go off either the MAF or o2.

 

Oh yeah, and I pressurized just the TB side because I was already taking out the intercooler to look at the blue T and inspect everything else and didn't want to go through the trouble of pressurizing the turbo inlet. Could be very convincing that I did not pressure test the BCS at all with this test as I only did a visual inspection. Next place I'll test is definitely BCS

[doobaruGT]

In for results!

 

 

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[turbo2]

In for results!

 

 

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As am I. Im just waiting for the problem to come back.

[Disgust]

Ok, so my BCS tested fine and I am dropping my car off to be pressure or smoke tested on Monday evening, so until then this thread will be pretty dead. I will update results when I get them though. I really have my money on something to do with the bypass valve or a brittle vacuum line that burst somewhere, but we will see what the pressure test has to say.

[doobaruGT]

Ok, so my BCS tested fine and I am dropping my car off to be pressure or smoke tested on Monday evening, so until then this thread will be pretty dead. I will update results when I get them though. I really have my money on something to do with the bypass valve or a brittle vacuum line that burst somewhere, but we will see what the pressure test has to say.

 

Sounds good. Could be something small, but with a leak like yours, I was expecting something more obvious. GL!

[Disgust]

Ok, I got back the news and it's a little interesting. First, my turbo is shot. The guy at the shop said it spins fine by hand and no shaft play yada yada, but it wasn't getting any oil and now the journal bearing doesn't want to spin at high RPMs. The guy at the shop was super nice and didn't even charge me anything to take a look at it. He said he just took off the intercooler and had his co-worker give it gas and there was NO air coming out of the turbo.

 

How and why I blew a new vf46: So this turbo is only 1800 miles old and went in to replace an old, whiny vf40. The reason it blew was like every other damn sudden subaru turbo failure OIL STARVATION. A month back, I got a strange code for my passenger side valve timing solenoid but at the time I was running dino oil and was getting a small hiccup about 5% of the time while accelerating, and thought nothing of it. Now, the shop tells me my oil feed line is leaking oil all over the turbo and the turbo is getting little to no oil. I don't think I caught this because I was working on the car at night and it hadn't been driving prior to me wrenching so I just thought nothing of it. Immediately, I understand my mistake. The valve timing code a month back was from a plug getting introduced into the turbo line and me not realizing and then continuing to drive on it. Then the plug moved up higher in the line until it finally got into the turbo and created enough back pressure to cause the high pressure line to leak and starve the turbo of oil.

 

What have I gained from this experience?

Don't be a dumbass if you have a CEL related to anything around the turbo oil feed line.

If you think your turbo is blown, it probably is.

If you refuse to think your turbo is blown, and then track down every leak in the turbo system, you will still have a blown turbo, but you won't have any boost leaks

Don't be an idiot when checking the turbo: This thing spins at like 80k RPM so if it "spins" by hand, it may still have an issue spooling to normal RPM.

OH yeah, and don't be an idiot.

Edited June 10, 2015 by Disgust

[turbo2]

Well.....shit. My turbo is on its way out....I guess its time to pull the trigger on an upgraded one sooner than I thought.

[Max Capacity]

Ok, I got back the news and it's a little interesting. First, my turbo is shot. The guy at the shop said it spins fine by hand and no shaft play yada yada, but it wasn't getting any oil and now the journal bearing doesn't want to spin at high RPMs. The guy at the shop was super nice and didn't even charge me anything to take a look at it. He said he just took off the intercooler and had his co-worker give it gas and there was NO air coming out of the turbo.

 

How and why I blew a new vf46: So this turbo is only 1800 miles old and went in to replace an old, whiny vf40. The reason it blew was like every other damn sudden subaru turbo failure OIL STARVATION. A month back, I got a strange code for my passenger side valve timing solenoid but at the time I was running dino oil and was getting a small hiccup about 5% of the time while accelerating, and thought nothing of it. Now, the shop tells me my oil feed line is leaking oil all over the turbo and the turbo is getting little to no oil. I don't think I caught this because I was working on the car at night and it hadn't been driving prior to me wrenching so I just thought nothing of it. Immediately, I understand my mistake. The valve timing code a month back was from a plug getting introduced into the turbo line and me not realizing and then continuing to drive on it. Then the plug moved up higher in the line until it finally got into the turbo and created enough back pressure to cause the high pressure line to leak and starve the turbo of oil.

 

What have I gained from this experience?

Don't be a dumbass if you have a CEL related to anything around the turbo oil feed line.

If you think your turbo is blown, it probably is.

If you refuse to think your turbo is blown, and then track down every leak in the turbo system, you will still have a blown turbo, but you won't have any boost leaks

Don't be an idiot when checking the turbo: This thing spins at like 80k RPM so if it "spins" by hand, it may still have an issue spooling to normal RPM.

OH yeah, and don't be an idiot.

 

Did you have the banjo filters removed before you put the vf46 on ?

Is this a 05-06 OBXT ?

[Boosted Red Wagonette]

This is a very old thread, but here in 2020, the wagon seems to be going through the same thing, I have to check hosing and all vacuum lines throughout the engine bay!

[Boosted Red Wagonette]

This is a very old thread, but here in 2020, the wagon seems to be going through the same thing, I have to check hosing and all vacuum lines throughout the engine bay!

 

 

Fixed now, turns out the intercooler hosing on the driver side was completely loose and unconnected, alongside a small bov vacuum line disconnected from under the tmic

 

 

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