Turn off engine and try to restart it, it will not start?

ANGELAWHITEHEAD

MEMBER
1997 SATURN L200
4 CYL
FWD
AUTOMATIC
12,500 MILES

My car with start just fine in the mornings or anytime that it has been sitting for awhile. But once you have driven the car for a while, turn off engine, and try to restart it, it will not start. You can wait about thirty minutes and then it will restart. What could be the cause of this? New brake, and new tune up within last six months. Please advise.

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

You have listed the vehicle as a 1997 L200, however Saturn did not make the L200 in 97. I have included the information on a 1997 SL2 for your reference.

This issue could be due to a faulty coolant temperature sensor.
It could be sending signal to the ECM that the engine is 'too hot' and triggering the no start, unless you wait certain period of time.
The coolant temperature changes its internal resistance with the temperature, that sends the signal to the ECM about the engine temperature. If the calibration is off on that sensor it can send wrong sigil and cause a no start.

You can test the resistance of the sensor between the pins. It will vary depending on the temperature (see chart below)

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 diagrams as well as the resistance range for that sensor.

Please let me know of any questions.
Thank you.

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