Boost control valve testing
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I think a a bad miss due to bad spark would cause low boost and my stalling issue (if the sparks totally stopped), but I think I would also hear it. It would also explain my P1300 and P1105. That sounds like a bad DIC or ECU. I need to get a Tech2.
However I should get more boost than none with an a really poorly running engine with the waste gate hose totally disconnected. I don't hear any misses, it just feels anemic and has no boost.
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I'll put my usual plug in for chinacardiags.com. About $300 shipped. $50 more with the case. Invaluable when you have one of these cars.
Bad ECU is very rare. Bad DIC is common. If you can swing the money, replace the DIC and keep the other one as a spare. I think everyone here carries a spare, LOL. Replace the plugs, either the stock platinum or BCPR6ES. Gap to .9mm. I would think you'd have more misfire codes with a bad DIC, but it can be unpredictable. Tech II will let you see misfire counts.
If you get the turbo fixed, you can try just the plug replacement first, properly gapped. That often ends DIC codes. But again, if you can afford a new DIC, it's not a bad move for a Saab owner.
P1105 "can be generated if the turbo is defective". (Download the WIS and install it...). So start with the turbo and see if that cures it. The other possibilities are leaks after the compressor.
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Just got my used turbo, the impellor vanes all look good and I don't feel any endfloat. However, I'd guess there's a half a millimeter of side to side float. I imagine this would diminish with oil and certainly with some oil pressure. Does this sound okay?
I had thought I'd swap this out and then rebuild my old turbo or get it rebuilt.in a year or two. It looks nicer outside than my old turbo. The housing and fittings have a bit less corrosion
I had thought I'd swap this out and then rebuild my old turbo or get it rebuilt.in a year or two. It looks nicer outside than my old turbo. The housing and fittings have a bit less corrosion
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If you put a feeler gauge between the very edge of the exhaust impeller vane and the housing, how much actual play do you measure? Also look for evidence that a vane ever hit the housing.
Ideally there shouldn't be any play, but as long as you have adequete clearance, you can use it. Most of these turbos have 100K+ miles on them, so finding one with zero play is unlikely.
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Half a mm is definitely normal. Do check out the hot side to be sure everything is intact, the swing valve moves freely, etc. Did the new turbo include its actuator? It so, I would test that with a pressure pump just to be sure the draphragm isn't ruptured. They're durable, but while it's easily accessible...
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I couldn't feel any difference when I pushed the vane toward my 0.002" feeler guage but I could feel some extra resistance with my 0.025" feeler guage. I felt a similar or slightly less amount of resistance when I pushed the other way and pulled my 0.005" guage through, and a bit more of tug with my 0.006" guage, so I'm going to say there's about 0.003" (0.08 mm) total side to side. That's not as much as I'd thought.
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That's not bad.
The other thing I like to check is to grab the shaft on both the input and output ends and wiggle it. You won't be able to measure like that as both hands will be busy wigglin'. You'd need an assistant.
But, the play you measured is the play on the output side so that doesn't really change if the input side has play too. It's just good to know.
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I'll give that a shot. The play I measured was on the intake air side of the new turbo.
I'm trying to do a pressure test.
I can't get my system to hold any pressure at all. I bumped my engine with the starter until cylinder 1 was over an inch from TDC. The engine has a 3" stroke but when bumping it with the starter and checking with a dowel I was seeing a maximum spread of 2.5".
I hear it leaking from around the throttle body. I'd think at this crank position there wouldn't be any valve overlap so it would hold pressure.
I didn't see any branding on my DIC, so I think it's a cheapo one. The plugs I had were NGK BCPR7ES. I think it should be NGK PFR7H-10.
I'm trying to do a pressure test.
I can't get my system to hold any pressure at all. I bumped my engine with the starter until cylinder 1 was over an inch from TDC. The engine has a 3" stroke but when bumping it with the starter and checking with a dowel I was seeing a maximum spread of 2.5".
I hear it leaking from around the throttle body. I'd think at this crank position there wouldn't be any valve overlap so it would hold pressure.
I didn't see any branding on my DIC, so I think it's a cheapo one. The plugs I had were NGK BCPR7ES. I think it should be NGK PFR7H-10.
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It definitely shouldn't leak from anywhere, so I'd address that first. I agree there shouldn't be much overlap at TDC, but you can always rock the crank back and forth a few degrees to trim down on it. I don't think you will, but you could reach the point where you hear air escaping through the exhaust. That's of course fine - any other leaks need to be dealt with. Make sure you block off the PCV system, of course. The leak from the throttle body could be the o-ring on the top. They are often in poor shape.
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I didn't disconnect the PCV system. Need to figure out where that is. Is this the o-ring you're talking about 9138702 by OES | O-ring
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You can run the BCPR7ES plugs. They are good for about 10 to 12 K. You can get four for about $10. You can also run the OG 9–3 spec PFR platinum plugs.They will last 50 to 60 K. They will cost about $50. So same long-term cost. A lot of us prefer the cheaper copper plugs because we want to be in there every year anyway. L O L.
If your DIC is non-factory, then it's definitely suspect. The aftermarket ones have a bad reputation. See the other thread on what's a factory DIC now for more info.
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Here's a picture of the underside of my Digital Ignition Cassette. I believe the NGK ones would say NGK on them somewhere.
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Definitely aftermarket.
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I was going to revisit the boost testing on my OG 9-3 after I fix some of my non-SAABs. Shouldnt the PCV valve be able to handle the 13ish psi of full boost pressure? I haven't yet fitted a guage to my test cap, but it doesn't seem to build any pressure at all before I hear hissing from the throttle body area.
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