my saturn all of a sudden decided that it will crank but won't start after 2-3 times. i bought a crank position sensor and i have no idea how to put it in, could it be the problem? and is it worth $74 for my mechanic to put it in?

 

Check to see if you are getting spark when it cranks but will not start. If you are not getting spark it COULD be the problem, but not necessarily.

If indeed you are not getting spark as described it's worth 10 min of your time to get under the car with a ratchet and socket to replace it....

 

so i installed the crank sensor and nothing has changed.. any ideas?

 

So are you getting spark?

 

If you are getting spark - think seriously about replacing the Engine Coolant Temperature Sensor (ECTS) - both the sensor itself, and the connector going to it.