Vapour lock or Stuffed DIC?

[millster]

Once again, my Saab is playing up.  This should be NO surprise by now.  It's well and truly summer in my branch of "the States" with temperatures averaging around 38C.  I got stuck in rare and nasty traffic today (the good news is, I've got the over-temp issue sorted) and with everything going great, I ended up breaking down on the downhill stretch of my trip very near home.  Luckily I was able to get off onto a slip road and out of traffic.

The fuel pump was running as expected and I could hear the DI buzz on key-on and after cranking, so I reckon I'm safe in assuming the DI is not the problem.  I called my Da to bring a snatch strap and get me home.  In the meantime, I proceeded to tink about and eventually got it fired up again.  I spun it about, back into traffic and thought I was right set... until it tucked out at the next intersection.  Since I hadn't made it far, Pop showed up, we drug it home and got it into the drive.  Hooked up the booster leads and it fired in a couple of cranks.  Sputtered a bit, but a good rev and she cleaned right up.

Doesn't sound of DI, eh?  Sounds like vapour lock to me, but I wanted to pass it by the lot of ya to see what you might think. 
I know VL is rather rare in pressurized fuel systems, but my non-return is stuffed (have a new one), the flower pot doesn't seal in the tank well (have been meaning to fix that) and my exhaust is split wide-open at the mid box which would put it dumping right at the fuel tank.  Seems like a perfect recipe for vapourized and non-pumpable petrol, yeah?

[900009]

crankshaft position sensor, 95% probability. When they get bad they fail when they get hot and come back to life when cooled down.

Next time it cuts out pour some water over your cps, wait a few minutes and see if she fires up again. CPS is mounted on the front side of the engine, under the exhaust manifold close to the gearbox.

[phoenix]

Yup, sounds like CPS. I'm not sure what the correct resistance is for a 9000, but on later models it's around 900 ohms.

[millster]

I had considered the CPS but summarily ruled it out when I noticed my tacho needle would rise when I cranked the engine.  In general, this would be contradictory to a dead CPS.  Of course if it's only partially packed-in then I suppose it could still signal the tach at the ECU but not provide enough signal to kick the ignition.

I suppose CPS is better news than the DI.  I'll check that one out.  Thanks!

[sgould]

I found this from a T5 9-3 Saab workshop manual...
(see attachment)

There are three terminals on the connector.  Only two show a resistance. Check those.

[Audax]

I had considered the CPS but summarily ruled it out when I noticed my tacho needle would rise when I cranked the engine.  In general, this would be contradictory to a dead CPS.  Of course if it's only partially packed-in then I suppose it could still signal the tach at the ECU but not provide enough signal to kick the ignition.

That's an old wives tale about the needle moving/not moving letting you know if it's the CPS or not. It can rise just it's reading incorrectly as it is out of specification. Test it for Ohms and have a look with an OBD reader if necessary.

[millster]

Thanks again, guys.  While it can't be conclusively ruled out, the CPS tested within spec and after replacing the one-way valve on the fuel pump and fixing the gap between the top of the flower pot and the lock ring, the car now starts within 2 cranks hot or cold and drove a solid 3 miles without so much as a stutter.  While I'm sure it had nothing to do with the random death yesterday I also fixed a nasty split PCV line I found while looking under the bonnet. 

So there we have it.  Looks like I fell victim to a fuel pump trying to push vaporized gasoline and not having much luck with it.