1999 Saturn SL1 Starting problems

The ignition control module was a expensive guess and they rarely fail on those cars. So it will crank and not start? Do you loose spark when it won't start? The most common reason for them to loose spark on those cars is bad crank shaft position sensors.I have replaced tons of them on those cars.

So when it doesn't start do you loose spark? Also when it won't start have you tried holding your gas pedal all the way to the floor while trying to start it?Another thing that causes no starts and tons of other symptoms is a bad coolant tempo sensor. I have replaced so many of those its unreal.

Then I would replace the coolant temp sensor sounds like its bad. When they go bad they always read the coolant temp lower the actual temp.I have seen some of them off by more then 100 degrees. Also inspect the inside of the connector going to it. If the terminals are blue or green instead of silver replace the connector also. Auto zone sells them for about 12 and has a lifetime warranty.

The engine coolant temperature sensor is a thermistor-type sensor. A thermistor resists the flow of electricity similar to a resistor. However, the resistance of a thermistor increases as the temperature drops.
So, by using multimeter it is possible to test that sensor, given the reference available for the temperature vs resistance chart (see below).

Here are some helpful articles:

https://www.2carpros.com/articles/how-a-coolant-temperature-sensor-works
https://www.2carpros.com/articles/symptoms-of-a-bad-coolant-temperature-sensor
https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

I have attached the replacement and the resistance chart for the coolant temperature sensor.

Please let me know if you have any questions.
Thank you.