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Discussion Starter · #1 ·
"High" is relative of course... ;)

Anyway, this just started last week. When I get close to the red bar in the "turbo" gauge, I get misfires. If I punch it, it'll buck and blow black smoke.

Turbo going out? I can't think of any way to get black smoke under those conditions. And it's not a puff. I can see a small cloud behind me when that happens. :(
 

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Most likely, the electronic boost control valve is failing. The ECU is reading an over-pressure situation and cutting the spark/fuel until pressure drops. That's the bucking as the ignition is cut. The black smoke is caused by raw unburnt fuel going out the exhaust and partially burning in the turbo or the cat-converter. You have two options;

A) replace the electronic valve??? last time I checked was $216 or $260 or something like that.

B) replace the valve with a manual boost controller, (ball-spring type) ~$100.

I had the same issue. I was able to extend the life of the failing electronic valve by spraying WD-40 into the orifices and banging on the table a few times to break free the solenoid. This is not a cure, it is a band-aid solution. As a long term fix, I opted for the less expensive manual controller. However with this option, the ECU has only the option of enriching the fuel mixture to control detonation. You must run premium fuel with the option to obtain full boost w/o damaging the engine. If you choose this option and wish to run regular or plus and not premium fuel you must limit the boost to 87 Octane ~ 5 PSI/.34BAR; 89 Octane ~ 8PSI/.55 BAR or you will get detonation and will damage the motor. 9.2:1 compression on B204L/B204R @ 1.0 or .73bar is either 14:1 or 12:1, compression under full boost depending if your have the FPT or LPT setup. I'm sure you can see how this can cause issues.
 

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Discussion Starter · #4 ·
That would be awesome if that's all it is. A boost controller for a couple hundred is WAY better than a new $800 turbo.

I don't have another DIC to swap with. Is there another way to test the DIC?
 

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I don't think it's fuel cut. Fuel cut is like hitting a wall. If it's just a misfire, odds are on the DIC or the plugs. Start with fresh, properly gapped plugs. Then try a DIC. If you can't borrow one, buy one. Every Saab should have a spare in stock.
 

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+1 on the freshly gaped plugs, you can get spark blow out if the gap is too big at higher boost levels.

You test the dic by removing it flipping it over and putting plugs in and grounding them, then check for spark at each plug when cranking. If you are only experiencing an intermittent or random misfire at higher boost levels, it probably wont show up on this test.
 

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Discussion Starter · #9 ·
Well, that was it! Sparkplugs!

The ones I pulled out looked like they were filed to a point. They were worn evenly, and had the usual orange/gray dust. They also had a gap that I could drive a truck through. :eek:

The only ones I could find locally were Autolites or Bosch. I went with the Autolites until I can order some NGK's. (Not a Bosch fan after seeing the jacked up threads on some of their plugs when I had my bus.) Gapped to .040 and test drove. Woot!!!

Ya know, I really should know better. Newly acquired used car, replace fluids and plugs unless maintenance records are present. I did the fluids but not the plugs. Feel free to smack me.

Thanks for pointing the plugs out!
 

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http://hawkworks.net/sparkplug-chart/
How long did the spark plugs last ?
Usually, this would be 15 to 30K, , I think 15 is closer to reality.
Don't forget the anti-seize and the silicone....:cheesy:;ol;
 

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"High" is relative of course... ;)

Anyway, this just started last week. When I get close to the red bar in the "turbo" gauge, I get misfires. If I punch it, it'll buck and blow black smoke.

Turbo going out? I can't think of any way to get black smoke under those conditions. And it's not a puff. I can see a small cloud behind me when that happens. :(
This should have generated a "CEL"....I would think....The black smoke is un or semi-burned gasoline...
The first thing to do is to bring all maintenance up-to-date.
 

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Discussion Starter · #13 ·
http://hawkworks.net/sparkplug-chart/
How long did the spark plugs last ?
Usually, this would be 15 to 30K, , I think 15 is closer to reality.
Don't forget the anti-seize and the silicone....:cheesy:;ol;
The worst plug gapped to .080, best one (in the pic) .072.

Those were the ones that came with the car so I have no idea how old they actually are. As I mentioned above, I should have done this when I bought the car, but it ran so smooth I was afraid to mess with it. ;oops:
 

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Discussion Starter · #14 ·
This should have generated a "CEL"....I would think....The black smoke is un or semi-burned gasoline...
The first thing to do is to bring all maintenance up-to-date.
I've never gotten a CEL. The light works, but nothing this car has done has triggered one...
 

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CELs seem to be pretty useless and I've only gotten them for O2 Sensors and nothing more serious than that. I had a similar symptom on my Viggen but the smoke was more grey. Turned out to be bad MAF. Glad I caught that really quick or I could have been looking at a new motor.

Be very easy on that car until you get your NGKs, they're really the only plugs that should be used as the ECU is calibrated for them to be able to properly read predetonation.
 

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Discussion Starter · #18 ·
<Sung to the tune of the Love Boat>

The FAIL boat
Is making another run...


The problem returned. Wasn't the plugs.

When I had the DIC off, I noticed a small crack between the #2 and #3 cylinders. So that's my next step, swapping in a DIC. As soon as I can afford one...
 

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Discussion Starter · #20 · (Edited)
No, I haven't had the money to buy a new DIC. And they seem to be few and far between at the pick your parts around here. :(

I did pull mine out yesterday. The black plastic has a crack in mine. However, I doubt it has anything to do with anything, as I removed the 8 screws and looked inside.

There are four coils, one that slides inside each tower. There's what looks like a relay and what looks like a transformer (I have no idea what they really are, that's just what they look like to me). The whole thing is filled with epoxy.

I was looking for signs of overheating, cracks, etc. I found nothing. Everything looks perfect in there.

So now I'm questioning the DIC being bad. I know stuff doesn't have to LOOK bad to BE bad, but I was hoping for some kind of confirmation.
 
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