Need to find location of coolant fan relay and sensor for 1990 pontiac sunbird ?

SOURCE: 99 cadillac de ville

the coolant temp sensor is at the rear of the engine and is a "bad word" to get to. the 3 relays are at the bottom,under the fans. if you remove the driver side fan out of the way( 2 10mm bolts holding the fan) you should have good access to them. they do have locks on them and may be tricky to unplug. there is a 7/16 nut holding the relay plate down. remove and it should be easy to remove them.

SOURCE: 1993 Pontiac Sunbird sensor location

Crank position sensor is located below #1 cylinder exhaust manifold side.

SOURCE: coolant sensor

According to mitchell on demand there is no low coolant tep sensor, only standard ECT sensor.

SOURCE: where is the coolant sensor located for a pontiac grand am gt

It looks like this with a connector to it and is on the side of the engine block:


Look right under the radiator hose.

SOURCE: location of coolant temperature sensor and

Removal & Installation To Remove:

1. Before servicing the vehicle refer to the precautions at the beginning of this section
2. Remove or disconnect the following:
   • Engine coolant into a suitable container to a level below the ECT sensor
     
     
   • ECT sensor harness connector (A)
   • ECT sensor

To Install:
NOTE: Use care when handling the coolant sensor. Do not drop damage to the coolant sensor will affect the operation of the fuel control system.
NOTE: Replacement components must be correct for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque which may affect the operation of the component. Use the correct torque specification when installing components to avoid damage.

1. Coat the sensor threads with GM P/N 1050805 sealer or equivalent
2. Install or connect the following:
   • ECT sensor
     1. Torque to: 15 lb-ft. (20 Nm)
   • ECT sensor harness connector
   • Engine coolant
3. Start the engine then idle until normal operating temperature is attained.
4. Recheck coolant level and top off as needed.
5. Test drive the vehicle.

--- I couldn't find a reference for the 'fan coolant relay switch' although I'm sure there is one on this car.