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Discussion Starter · #1 ·
My Saab 900 NG (1996 SE 2.0 Turbo convertible, 160K miles -- actually my daughter's as I now have a 1997 93) is having a fuel system problem and I could use some help diagnosing it.

The problem is as follows:

After the car has sat for an extended period of time, e.g., 5-10 hours, overnight, it is extremely hard to start. It takes 6-15 extended cranks of the engine to finally get it to sustain rotation. Up to that crank that gets it over the hump, it'll start to turn over normally, then die, sometimes/oftimes "coughing" before dying.

My daughter claims that once running, it has low power for a few minutes then runs and starts normally the rest of the day. (only a teenager would assume that this would be perfectly acceptable state for the car).

I have done a cursory inspection of all the vacuum hoses and haven't found an obvious leaking one yet (haven't checked the expansion chamber element behind the wheel well splash guard yet). No fuel leaks that I can determine either. FYI, I replaced the fuel pump about 20,000 miles ago, and though I have replaced most of the vacuum hoses over the years for various leaks (which never affected anything other than the check engine light), but I have never had the throttle body or injector rail off.

Any idea what the problem could be? I thought that the rough running could be a bad injector or two but that wouldn't explain it eventually running OK after warming up, would it?

Any help with a diagnosis plan would be greatly appreciated.
 

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If you have a leaking fuel injector ( or two), when the engine sits over night, fuel may be leaking into the cylinders, effectively flooding it. You could test this theory by just watching the exhaust pipe in the morning. Any black smoke would indicate too much gas.

You could also check the plugs in the morning to see if any of the plugs have excess gas on them... Ron
 

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First, have you done all the basics: new plugs, air filter, fuel filter, checked and replace small vacuum lines, cleaned throttle body, cleaned IAC, etc. That's always the best starting point. You should also try a spare DIC.

With it dead cold, try spraying starter fluid down the throttle body, (step back), then try to start it. If it fires, then you have a lack of fuel. If not, it's something else. That will at least eliminate the "lack of fuel" issue.
 

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What';s DIC? Ignition Cartridge? If so, then that was replace less than a year ago.
Was it a genuine replacement? If so, odds are it's still good. If not, I'd be thinking of testing with another one just to be sure. The Chinese versions have failed in a short time.
 

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Others have reported a one year life for those. Not saying that's absolutely it, but you should test with a good DIC and see if it improves.

If it is the DIC, report back, we need more feedback on the Chinese DICs.
 

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Discussion Starter · #9 ·
OK, after going step-by-step thru 20+ checks, and then starting back thru the list again, the problem turned out to be the DIC -- one of top 5 items on the checklist. It worked fine when upside down, but only intermittenttly when "right-side up". Didn't believe the DIC mythology: strange but true. And yes, the failed DIC was one of the cheap Chinese ones from eBay. Lasted barely 15,000 miles.
 
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