1999 Saab 9-5 start problems (especially when warm??!)

[Kobs84]

Hello all. I'm new to the forum here and not much of a mechanic myself, so I hope someone can point me in the right direction with the issue I'm having. I've had a problem with the car for quite some time now, and today when my wife was going to take the car to work it didn't start at all. All the lights are working when I turn on the ignition, but when I actually try to start it everything just goes black. Usually it always starts, and driving is fine, but what has been a common occurance for some time now is that it always starts perfectly when the engine is cold. However if it is warm, and I try to start it, I have to help it with some throttle, otherwise it shuts down. And as I mentioned, this morning it did not start at all.. I may add that the battery was changed about 1,5 years ago, and the plugs have also been changed recently. Hope someone can help with some tips

[S442]

Hi.

Maybe is throttle position sensor. Get to the shop and plug it on computer to tell you more.

[DanielZ]

Could it be the cps? Easy and cheap thing to change.
Mine always turned over and never went black, but similar to your case it began with ok starts when cold and never when hot/warm. Then it refused to start at all. Battery change did nothing.
The sensor is fiddly to get at but with the propper extensions it's an on the driveway job. I did a writeup of how i did it. Some say it's easier from below but I dunno how many more elbows you need to do that...

[Djoreem]

Hello,

I have been experiencing similar problems in my '2000 automatic 9-5.
In the first months I would try to start the car after a short trip and it would not react at all.
After the engine had cooled off, say 30-45 minutes it would fire up again as if nothing was wrong.

After 6 months this problem gradually got worse, untill the point where it would even shut down whilst driving.
Especially after being in a traffic jam or whenever the engine heated up the engine space to much.

(Normally, the starter wouldn't budge, but in the last few weeks it occasionally happened that the starter engine would turn over, but no egnition this time!?!)

Her's what i ve got for you so far:

The DI cassette: kinda wears out every 150k kilometers, which is normal.. few hundred bucks gets u a new one, BUT:
never replace it without also replacing the spark plugs, one falty plug can fk up your new DI cassette in no time! (even in a new set of spark plugs there can be one that"s flawed, so have them measured out before installing them.)

The CPS: (Crank position sensor ) is a relatively cheap thing to replace, but only reachable from underneath, not rocket science, just a bit of finger wrestling,
get the right tools to acces it! If you don't want to do this yourself, know that your mecanic shouldn't charge much more than an hour for this.
again, say about 200 bucks this way.

The solenoid: A small easy to reach part you can find online for about 80 bucks, it is a magnetic switch, that when soiled could become temperature sensitive.

So far, i have replaced these 3 parts and the car was operating perfect again.... for about a week!
Today the problem resurfaced and i am now looking into troubleshoots about the mass cable connection, tension could be insufficient due to a falty closing of this circuit,
again; dirt, rust, temperature, vibrations can all mess with the connection points that close this circuit of tension around the frame and the engine...
let you know how that works out!

good luck, #stilllovinthesaab

[DanielZ]

The CPS: (Crank position sensor ) is a relatively cheap thing to replace, but only reachable from underneath, not rocket science, just a bit of finger wrestling,
get the right tools to acces it! If you don't want to do this yourself, know that your mecanic shouldn't charge much more than an hour for this.
again, say about 200 bucks this way.

I can change it from the top in about 15 minutes. If you remove the front heat shield, battery and the battery tray/rest plate you will be able to reach it. Then you just need a wrench with the correct length and you will be able to get the CPS out. it's fiddly but a drive-way job.