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Discussion Starter #1
I learned with my NG900 that starting it briefly, say to move it in the driveway, and then turning it off for the day, was not good. The car would be unhappy starting the next day. Never any problem if turned off after a few minutes running, or if started briefly while warmed up, but short start when cold made it not want to restart.

Well, that was a non-turbo Motronic.

I briefly started my 9-5 yesterday to put it in the driveway. It ran for maybe 60 seconds.

Today, it didn't want to start. Or more accurately, it caught, then died. This happened twice. I tried cranking with the pedal to the floor, and it just cranked and cranked.

Then about fifth try, as I was about to hook up the Tech II, it started and ran just fine. No problems restarting it since then.

CPS is good, I did notice that the tach dropped when I cut the starter after some fruitless cranking. Fuel pump was replaced a few years ago. The headlight auto adjusters are noisy enough to drown out any fuel pump sounds.

Anyone else run across this problem? It seems to be a Saab problem, if not EFI in general.
 

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2005 9-5 Aero
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I learned with my NG900 that starting it briefly, say to move it in the driveway, and then turning it off for the day, was not good. The car would be unhappy starting the next day. Never any problem if turned off after a few minutes running, or if started briefly while warmed up, but short start when cold made it not want to restart.

Well, that was a non-turbo Motronic.

I briefly started my 9-5 yesterday to put it in the driveway. It ran for maybe 60 seconds.

Today, it didn't want to start. Or more accurately, it caught, then died. This happened twice. I tried cranking with the pedal to the floor, and it just cranked and cranked.

Then about fifth try, as I was about to hook up the Tech II, it started and ran just fine. No problems restarting it since then.

CPS is good, I did notice that the tach dropped when I cut the starter after some fruitless cranking. Fuel pump was replaced a few years ago. The headlight auto adjusters are noisy enough to drown out any fuel pump sounds.

Anyone else run across this problem? It seems to be a Saab problem, if not EFI in general.
I had that happen a few times over the years. could never understand why it happens. It's almost like it's expecting a certain cycle and it just doesn't happen how the car wants it to.

Just curious, what does putting the pedal to the floor do?
My car is on my driveway now, I'm still trying to figure out what the heck is going on with it lol.
 

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Discussion Starter #3
Pedal to the floor clears flooding. Although, it probably has to be put to the floor while the car is on. I'm not sure I did that.

This is the first time I've moved the car without driving around the (short) block just to get it running a bit longer. And I guess the last time.
 

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SAAB 95 2004 Linear Wagon
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with your current issue, the first initial engine start would use the "normal start procedure" from the ECU with its programmed fuel/air mix setting for a "cold start", and letting the engine run for 60 sec or so could give just enough time for it to start warming up. on the next start later that day, the engine temp sensor information is slightly different, and the ECU would calculate a slightly different fuel/air mixture for that start setting, which in this case causes the no start gremlin to appear.

maybe the next time you notice the same conditions/elements, and you notice the "later re-start problem", dont keep repeat cranking it for the next 10 or 15 min till it eventually starts (as you seem to describe ?). try instead to disconnect the battery for 15 min or so. from my past experience this seems to force the ECU into a more aggressive start setting (and wipes the old learned mixture setting for that driver), i suspect it will start promptly and would confirm the ECU is overriding minor information errors from other sensors that are causing your re-start problem issue.

to then identify the sensor or electronically controlled element that is the actual cause is the harder part :) (eg engine temp setting, small air leak in the fuel system or a slightly leaking injector etc..). the ECU reset trick might however give you a reliable way to start the car and help in narrow down the causes ?
 

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Discussion Starter #6
Coolant gauge works perfectly. No codes pending or otherwise (I put on the Tech II later). Car starts and runs fine under all other circumstances. Cold starts, warm starts, or starts after it's only run a few minutes from cold and then shut down.

The really odd thing is that my Motronic NG900 behaved the same way. I learned to let it run at least a minute or two after a start.

I will say that I have no idea how it will behave if I shut it down too soon, and then try a restart after only a brief pause. I suspect it will be fine. This only happens with a short start, then leave it for at least hours, more likely overnight.

I'll just go back to driving around the block if I'm pulling the car in from the street. That seems to work fine.
 
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