Lately car has been "rough" to start

[robhurlburt]

So this has happened twice

- Get in car and turn key
- Car turns over fine (seems like plenty of battery power), and sort of catches and dies. Stutters REALLY hard.
-Turn key again, turns over fine, and jam on the gas pedal. Car fires up, little rough for a second or two, then levels out fine.
- this morning it was rough at start for a second or 2.

Does anybody have any ideas besides the battery? It turns over no problem, but the first couple of fires of the cylinders is rough, almost like it miss fires. Battery has 14.3v at idle, 12 or so shut off. No CEL, no SID message.

It is very random, and has one had 3 rough starts over the past 3 weeks or so.

[Geeves]

Mine does that if i move it quick the night before. Like if i only let it run for 40 deconds then shut it off the next start is always a problem.

[robhurlburt]

Thanks for the reply, but it has done it twice after work (drove 11mi b4 shutdown), and once in my driveway (drove 2mi before shutdown).

Are you not wondering why it does that?

[DougR]

Originally Posted by robhurlburt

Are you not wondering why it does that?

He has obviously driven a previous saab

After owning other saabs, I can't say that I would be really freaked out by that happening to my current one, but I would be worried if it happened to my other car which isn't a saab.

[Ridenbaugh]

Air filter and spark plugs good? I've never had this happen to my Saab. Maybe a fuel pressure issue? Maybe crankshaft position sensor on its way out. Really these are just guesses maybe it will help stimulate better thoughts for someone.

Originally Posted by robhurlburt

So this has happened twice

- Get in car and turn key
- Car turns over fine (seems like plenty of battery power), and sort of catches and dies. Stutters REALLY hard.
-Turn key again, turns over fine, and jam on the gas pedal. Car fires up, little rough for a second or two, then levels out fine.
- this morning it was rough at start for a second or 2.

Does anybody have any ideas besides the battery? It turns over no problem, but the first couple of fires of the cylinders is rough, almost like it miss fires. Battery has 14.3v at idle, 12 or so shut off. No CEL, no SID message.

It is very random, and has one had 3 rough starts over the past 3 weeks or so.

[Mithos the Hero]

Any bad smoke or anything out the pipe? Sometimes O2 sensors can go and throw the MAF off. Or even the MAF, though these generally give CELs, but riden i think is mostly on track. I'd say pull the plugs right after it stalls the first time. Could be coil packs or plugs, which would leave a horrible gas smell since they are igniting improperly. Also points to see are. Pull off the intake hose, see if there is a lot of deposits on it or the throttle position switch could be going. Sadly there is a lot of points to look up.

If it clears up as it runs you might wanna take it to an indy shop with a tech 2. They should be able to pull up most of the specs as it runs.

[robhurlburt]

Originally Posted by Mithos the Hero

Any bad smoke or anything out the pipe?

not that i noticed

Originally Posted by Mithos the Hero

I'd say pull the plugs right after it stalls the first time. Could be coil packs or plugs, which would leave a horrible gas smell since they are igniting improperly.

you mean the spark plug will smell like gas?

Originally Posted by Ridenbaugh

Air filter and spark plugs good?

new filter and plugs @ 70Kish. Filter was switched to a DIY intake FWIW. It has 78K on it now

Originally Posted by Ridenbaugh

Maybe a fuel pressure issue? Maybe crankshaft position sensor on its way out.

any way to check these?

Its so random, I doubt it will happen when i bring it to an indy, so is there anything they can even do?

[Ferms_93_2.8T]

Is it possible that I remember reading one time that some 9-3's had an issue where fuel was left in the system once it was turned off. I guess like a flooded carburetor. But obviously different. Maybe it is a throttle body issue.

[Ridenbaugh]

This might explain why he needed to floor the pedal to get it to start. It seems like I saw somewhere that if the engine for some reason gets flooded you need to push the pedal to the floor. Can anyone confirm this?

The OP, as far as checking those items I'm not sure how you would do this. Perhaps checking voltages? But, usually I think with a bad CPS the car won't even crank at all nothing at all happens, I believe it also causes stalling issues with no restart after the stall. Maybe you could google the topic and signs of a bad one. As far a fuel pressure, I really don't know. If the car ran poorly and continued to run poorly this may be more of an acceptable idea. Honestly, since you don't get any CEL codes its hard to know where you should start looking, so basically you would have to wait till the problem gets worse or start taking stabes in the dark... sorry I can't be more helpful

Originally Posted by Ferms_93_2.8T

Is it possible that I remember reading one time that some 9-3's had an issue where fuel was left in the system once it was turned off. I guess like a flooded carburetor. But obviously different. Maybe it is a throttle body issue.

[mrbrett]

I have read that holding down the gas pedal upon startup in a fuel injected vehicle actually shuts off the fuel flow. If the car was flooded previously, this would theoretically make it easier to start.

[SAABRoma]

Originally Posted by Ferms_93_2.8T

Is it possible that I remember reading one time that some 9-3's had an issue where fuel was left in the system once it was turned off. I guess like a flooded carburetor. But obviously different. Maybe it is a throttle body issue.

Well, couldn't you check that hypothesis by revving the engine and cutting ignition around 3000rpm ?
Same as what they do for WW2 propeller driven planes during the shutdown procedure. Engine keeps spinning and evacuating exhaust(excess fuel in this situation) as it does during the 4th stroke, but no additional fuel is going into the system.

[ctrlz]

Look for a vacuum leak. Check here first:
http://www.saabcentral.com/forums/sh...d.php?t=151261

[robhurlburt]

much appreciated. I will check for the leak. I guess i wil just have to wait and see if it gets worse. Could be gremlins

[ctrlz]

Originally Posted by robhurlburt

much appreciated. I will check for the leak. I guess i wil just have to wait and see if it gets worse. Could be gremlins

Let me know what you see. I strongly suspect everyone and his brother will have at least a cracked hose in that spot, if not a leak.

[robhurlburt]

Originally Posted by Geeves

Mine does that if i move it quick the night before. Like if i only let it run for 40 deconds then shut it off the next start is always a problem.

ok, i moved the car from the street to my driveway last night. did it this morning. LOL

i still have to check for the leak

[ctrlz]

Originally Posted by Geeves

Mine does that if i move it quick the night before. Like if i only let it run for 40 seconds then shut it off the next start is always a problem.

This is caused by fuel condensation on the cylinder walls. The engine is not running long enough to heat up even the cylinder. The rich mixture condenses. The next morning you can't start the car because the cylinders are gas-soaked. Very common problem with injected cars. Solution is to let it run for at least a few minutes.

[pacotaco]

maybe maybe maybe crank sensor when those get dirty they can have a bog effect where it throws off the timing or or or maybe iac im not completly shure if the saab has one but iac valve you can try and clean that and or adjust that

[robhurlburt]

ok, i am going to autozone at lunch today to fix the cracked vacuum line. It did it again this morning.

When I slam on the gas pedal to get it going, it makes a sound like it is backfiring/popping once or twice before it fires up. Before it was a fluke, now its almost every morning

[robhurlburt]

well, after some reasearch I have heard of one thing that may cause it. If its warm in the day, and cool at night, condensation could build up in the intake tube causing a rough start. Has anybody with an aftermarket intake had this issue?

[robhurlburt]

changed the VAC line last night, but it wasn't cracked all the way through. sure enough, started like crap this morning.

I guess i will try starting it without the MAF plugged in. Going to the dealership at lunch to see if they have any ideas.