Check engine light goes on...code says coolant sensor...have changed it twice and it still comes on.

Have the codes read. I haven't worked on any thing to date that reduce power because of the coolant system or the oil. I have done some that will kill the engine because of both, but not reduced power. This could be from an engine hard part, sensor or wiring. Most times it's caused from a transmission problem.

The coolant temperature sensor may cause the light to come on. when the sensor fails the engine is slow to start and there is a strong odor of gasoline. turn it off and it starts normal the second time.

This also happened to me and it was the heater matrix, whatever that is

code p0118 refers to engine coolant temperature (ETC) sensor ---circuit malfunction===causes---coolant thermostat---wiring open circuit/short to positive---wiring short to ground---ground wire defective---ECT sensor.. The temp gauge works off a temperature sender unit separate to the coolant sensor and if it is reading 100 then it indicates an overheat situation in the engine . Probably why the engine light is coming on. As the thermostat is in the list of causes I would replace it as a precaution. The coolant sensor is what tells the CPU to turn on the electric fans to cool the radiator

not the pump but air in the system or a broken wire to the coolant level sensor
that sensor at the top of the radiator tank has to be completely immersed in coolant or the circuit is broken and the light comes on
same effect id the wire to that sensor is broken in the insulation

There are several codes for the sensor. I would need the exact code to help you. Are you getting 'insufficient temperature for closed loop operation?'

did you change the sensor? Did you top off the system?


Is there a coolant leak?

If the "check engine" light is coming on, there is a code, even though the light goes off, the code should be stored. If it stays in 1st gear I'm guessing you may have a stuck shift solenoid. Have you had the trany fluid changed lately, is it full of fluid? Check the fluid with vehicle in "park" on level ground, with the engine idling, it's best to do this at operating temperature. The manufacturers usually recomend changing the fluid and filter every 30,000 miles. It could be something else too the transmission shifting is controled by the computer. The computer gathers information from various sensors on the vehicle and tells the transmission when to shift. I guess I would get it to a shop and have the codes read to find out what is going on before you have major trany problems. It could be the vehicle speed sensor, throttle position sensor, mass air flow sensor, coolant sensor, etc. Good luck.

Replace sensor in bottom of coolant resevoir ( like overflow bottle)

Code P0132 is O2 sensor voltage high bank1 sensor 1, P0137 is O2 sensor voltage low bank 1 sensor 2, P1189 indicates a fuel control problem bank 1. It could be either the O2 sensors or a convertor. Could also be intake manifold gaskets. GM had a lot of problems with the lower intake gaskets leaking on the 3.1 and 3.4 engines that was linked to their Dexcool coolant. In fact they just lost a class action lawsuit about it. check with the dealer and see if the intake problem has been taken care of. Hope this helps.