[ewgoforth]

I'm trying to troubleshoot low boost on my 2000 9-3 SE (b205r).

I've seen some contradictory information on troubleshooting. If I disconnect the electrical connector will the waste gate stay shut?

I'm Checking the bypass valve (B235R, B205L/R) – 9-3 2000 | SAAB Workshop Information System Online it talks about troubleshooting the Checking the bypass valve (B235R, B205L/R). Is this the vacuum operated part that actually connects to the waste gate via the pushrod?

I assume that if I disconnect the vacuum line from the part that actually connects to the waste gate via the pushrod that the waste gate that the waste gate will remain closed also.

Thanks,
Eric

 

[ewgoforth]

Nope, car is in base boost mode.

In both scenarios I listed it will be in base boost mode?

Is there a way to fully close the waste gate?

Is the "bypass valve" the vacuum operated part that actually connects to the waste gate via the pushrod?

Also in Basic boost pressure control valve setting – 9-3 2000 | SAAB Workshop Information System Online it talks about a seal on the pushrod. Is this seal something to indicate tampering with the boost or is it a seal to prevent leaks, etc?

 

[ewgoforth]

Im seeing a max of 1 psi on a cell phone app from my OBD2 adapter. I wonder if this would be from the MAF sensor or actual manifold pressure. It reads inches of vacuum at low throttle then psi of boost at higher throttle.

It sounds like disconnecting the electrical connector on the boost control valve would have me at base boost and disconnecting the waste gate vacuum hose (from either end?) will totally disable the waste gate?

 

[ewgoforth]

That's correct.

It's hard to guess what a generic OBDII adapter shows. My Scangauge will display MAF in g/m and MAP in psi, but I have no way of knowing whether those are actual sensors or calculated values. I assume sensors but I don't know. This is an area where Tech 2 is helpful. It can also show MAF deviation, which tells you the variance of measured and corrected mass air... it's very helpful for diagnosing failures.

If you are actually getting 1psi, that is below base boost. The only way to get that is if the turbo's wastegate or actuator is defective or the engine is running real bad or there is a massive air leak. You can check the first with a Mityvac and a visual inspection. Second doesn't sound like it's the issue. Unhooking the W port will test the third, so would a smoke machine or intake pressure tester, either of which are the far safer options.

My initial problem was my car wouldn't start when it stalled out. Initially it sounded like a crank position sensor. Then it died while driving on the highway showing a P1105 and a P1300. Now the turbo is very loud and doesn't seem to have any boost.

I wouldn't think a massive boost leak would stop the car from running altogether, maybe I have more than one problem.

I think I'll look at the boost issue now since it's reproducible. I've seen some videos on how to make a a boost leak detector. It looks like I also check the waste gate and end play of the turbo without removing the turbo from the car.

I've had the car a month or so, it ran pretty good for several hundred miles. I got 32 mpg driving it from Virginia to North Carolina. It seemed to have similar power to my wife's 2004 9-3 convertible.

 

[ewgoforth]

Is the wastegate actuator still attached to the wastegate. That P1105 almost sounds like the code you get when the clip holding the actuator onto the actual wastegate lever falls/rots off allowing the wastegate to get stuck in a fully open position.

The wastegaye linkage is still there. I tried disconnecting the electrical connector to the bypass valve and got no boost. I tried disconnecting the W vacuum line from the bypass valve and got no boost (do I need to plug the line or cap the hole in the bypass valve when I do this?) . I think I have a big air leak ( although everything LOOKS OK) or a dead turbo.

I assune the wastegate and divertor valve shut when at rest, like when the engine isn't running. Is this correct?

 

[ewgoforth]

You're saying bypass valve, but I think you mean boost control solenoid, true?

I got bypass valve from the WIS. It's the divertor valve Checking the bypass valve (B235R, B205L/R) – 9-3 2000 | SAAB Workshop Information System Online

 

[ewgoforth]

Reach down where the hose that comes from the intercooler and goes to the charge air pipe is and check it with your hand. Looking isn't good enough because when it blows off, it stays roughly in place but spews all your charge air under boost .

You don't need to plug the W line. It's blowing air out, not pulling it in. You can if you want to but it shouldn't matter in the context of testing the turbo hardware.

Wastegate is shut when engine is off. Or at least it should be. Reach down there and try to move the lever. It should be very hard to pull. When the engine starts, it should stay in the same position with the W hose disconnected.

If you want to actually see the wastegate to verify if it's closed or open, you would need to remove the downpipe. That's only three nuts on the turbo studs, but if they haven't been off in a long time they can be a real PITA - especially the bottom one on your T7. You need a short handled 13mm wrench and some time. It's usually about 1/8 turn at a time, flip the wrench, another 1/8 turn, etc. A small MAPP gas torch helps. Soaking with PB Blast or Kroil or similar over three days before helps.

When you write "the hose that comes from the intercooler and goes to the charge air pipe" I assume you mean on the discharge side of the intercooler? I tried tugging on the hoses that connect to intercooler on both the input and discharge sides and they both felt firmly attached to me.

I tried moving the waste gate lever. I couldn't move it toward the diaphragm box but could get it to move away from the diaphragm box with some difficulty. I believe pushing the waste gate lever toward the diaphragm box would be closing it and away would be opening it, so it seems okay at first glance.

I plan to check the waste gate and the endplay on the turbo after I change a power steering hose on our MDX.

 

[ewgoforth]

There's no electrical connector on the bypass valve...

There is an electrical connector on the boost control solenoid, and an electrical connector on the bypass valve control solenoid... I'm not sure which we're talking about.

You're right I meant Boost Control Valve or Solenoid valve.

 

[ewgoforth]

That is backwards.... the wastegate arm should move towards the actuator (opening the wastegate) not away from the actuator (closing the wastegate). It's really difficult - borderline impossible - to move by hand. I would maybe see if you could borrow a pressure pump (like a Mityvac) from an auto parts store if you wanna accurately test this.

Assuming that it's vacuum operated and not pressure operated it would make sense for the arm to move towards the actuator, since it would be sucking the internal diaphragm that way.

I have a mity vac that I mostly use for bleeding brakes. I'll hook it up and see what happens.

I guess I can do the vacuum test on the Bypass valve too while I'm at it.

 

[ewgoforth]

Assuming that it's vacuum operated and not pressure operated it would make sense for the arm to move towards the actuator, since it would be sucking the internal diaphragm that way.

I have a mity vac that I mostly use for bleeding brakes. I'll hook it up and see what happens.

I guess I can do the vacuum test on the Bypass valve too while I'm at it.

I hooked up my mighty vac to the actuator and it didn't move when I pulled a vacuum. I could move the the wastegate operating lever away from the actuator but not towards the actuator. I believe that the actuator's vacuum would pull the wastegate operating lever away from the wastegate and that a spring inside the actuator would push it shut it seems like maybe the actuator or the waste gate itself are stuck in the open position somehow. It looks like wastegate actuators are no longer available and I don't see a part number for replacement doors?

If I pulled the wastegate actuator off the car I should be able to push the pushrod into the unit slightly and a spring would push it back, right?

My mighty vac doesn't have a gauge on it but when I hooked up it to the wastegate actuator and to the diverter valve it made a sucking sound when I disconnected it after a few seconds so I could tell that it was pulling vacuum on the two components.

 

[ewgoforth]

If it's pressure operated then I would think it would push on the operator rod, not pull, and so the wastegate lever would push to open the wastegate as well.

 

[ewgoforth]

If there's pressure inside the wastegate actuator then I should think it would have to push open the wastegate, not pull the door open. Talking about the part that actually opens and closes the wastegate, not the solenoid.

 

[ewgoforth]

Have you checked inside? I found the waste-gate flapper rotted right off the
stem on my '99 9-3

Hopefully I'll be able to check this weekend. Are the wastegate doors/flappers available? I haven't seen them anywhere.

 

[ewgoforth]

Are you talking about the actual wastegate or the actuator? The wastegate is part of the exhaust housing on the turbo... the actuator is a separately replaceable part.

I'm talking about the actual wastegate. Wondering if it's bad if I can replace it.

 

[ewgoforth]

I'm going to look into the turbo, based on what I find there I may want to pressure test the system.

I've never done this before but based on some YouTube videos that I've watched I was planning to disconnect the snorkel from the air box and make a cap from PVC.to fit in it.

I'd then fit a Schrader valve in the cap and pump it up to 20 psi or so and see if I have any leaks. Are there any components that I should disconnect to prevent damaging?

I think some people run over 20 psi boost. I haven't found a max boost spec in the WSI, I guess it varies depending on octane, etc. I was thinking about 1 atmosphere (14.7 psi) would be normal? Base boost pressure is 6.5 psi.

 

[ewgoforth]

I'm going to look into the turbo, based on what I find there I may want to pressure test the system.

I've never done this before but based on some YouTube videos that I've watched I was planning to disconnect the snorkel from the air box and make a cap from PVC.to fit in it.

I'd then fit a Schrader valve in the cap and pump it up to 20 psi or so and see if I have any leaks. Are there any components that I should disconnect to prevent damaging?

I think some people run over 20 psi boost. I haven't found a max boost spec in the WSI, I guess it varies depending on octane, etc. I was thinking about 1 atmosphere (14.7 psi) would be normal? Base boost pressure is 6.5 psi.

In the first step of the WIS Checking the wastegate (B235R, B205L/R) – 9-3 2000 | SAAB Workshop Information System Online

It says:

Detach and move aside the bypass pipe with valve.

If I understand correctly, that's on the inlet side of the turbo. Any idea why they want you to do this? is it just to give you more room to work?

 

[ewgoforth]

Yes, just to give you room to work. It's the aluminum tube running from the bypass/recirculation valve to the turbo inlet pipe. There is a o-ring on the inlet pipe side.

I got the exhaust pipe off the turbo. The nut on the bottom was a real bear, badly rounded off. From what I can tell the wastegate looks good, like a healthy exhaust valve. I could spin it around. I tried feel it's seat and it felt okay. The turbine felt alright, spinning freely with no detectable end play.

I was kind of expecting some noticeable damage. I wonder what the loud whining sound and low boot could be due to. I think I'm going to need to do a pressure test.

I'll see if I can get some pict tomorrow.

 

[ewgoforth]

Yes, just to give you room to work. It's the aluminum tube running from the bypass/recirculation valve to the turbo inlet pipe. There is a o-ring on the inlet pipe side.

I got the exhaust pipe off the turbo. The nut on the bottom was a real bear, badly rounded off. From what I can tell the wastegate looks good, like a healthy exhaust valve. I could spin it around. I tried feel it's seat and it felt okay. The turbine felt alright, spinning freely with no detectable end play.

I was kind of expecting some noticeable damage. I wonder what the loud whining sound and low boot could be due to. I think I'm going to need to do a pressure test.

I'll see if I can get some pict tomorrow.

 

[ewgoforth]

I got the exhaust pipe off the turbo. The nut on the bottom was a real bear, badly rounded off. From what I can tell the wastegate looks good, like a healthy exhaust valve. I could spin it around. I tried feel it's seat and it felt okay. The turbine felt alright, spinning freely with no detectable end play.

I was kind of expecting some noticeable damage. I wonder what the loud whining sound and low boot could be due to. I think I'm going to need to do a pressure test.

I'll see if I can get some pict tomorrow.

The wastegate looks okay, but I think there's a part of a blade missing on the exhaust side of the turbine. I would think that would throw off the balance of my CHRA, but wouldn't think that would totally kill my boost. I have no boost and a loud whirring noise.

I"m not clear on how to take off inlet pipe. It appears that I'd need to disconnect the bypass pipe and disconnect the hose clamps at the top and bottom. What is the fitting to the left of the solenoid valve in this picture:

 

[ewgoforth]

I'd think on the exhaust side that it would probably be in the catalytic converter. I'd think if the inlet side is okay my engine didn't likely eat anything. A compression test might be good to do as a sanity check.