QuestionI have saab 900s 1990. Recently it started to acting up. It stalls on me few times without warning, just dies without any straggle. It has a tendency to start again after 15-30 minutes and runs great like nothing happened. But not this time. I can hear fuel pump buzzing, starter motor is working, but engine would not turn over. Last two times, car stalls after idling for five minutes.
AnswerGeorge:
The symptoms described can be from several causes, in order of likelihood:
a. Electrical (spark generation) system
b. Fuel mixture circuit
The first step in problem isolation is to identify which of the above is at fault. One way to do this is to spray starting ether into the intake just before attempting to start. If this has a noticeable effect,(the engine starts) then fuel is the problem. If not, then focus on the spark "side".
If due to fuel, you'll need to check the idle control valve for free movement, the temp sensor for the correct resistance, and the fuel pressure regulator for the correct pressure. If so inclined, I recommend subscribing to <www.alldatadiy.com>, a web site that has detailed troubleshooting & repair instructions for you to follow.....$25/year/vehicle, but well worth it.
Likewise if electrical, you'll need to check the crankshaft position sensor, spark electronic module, coil, distributor, hv wires, %26 rotor. Again, detailed instructions are fully addressed in the above website.
