Engine light

[Amanda frost]

Hi all we have a vx commodore, the car was over heating when we idled for to long then if we turned the heater on it would go back to normal, so we changed the water pump and the thermostat and that seems to of fixed it but now the engine light comes on for about 10 seconds then goes off when it does that the temp gauge drops to cold and the kicks back in and sits at its normal spot has anyone experienced this or could they point us in a direction to check anything we need to car is running fine many thanks

 

[ltdslip]

V6 I assume?
Can you get the car scanned for fault codes?
Check the engine coolant temp sensor , connector for cleanliness & security.

 

[Lex]

Have you bled air out of coolant system?

 

[Fu Manchu]

Coolant temp sensor.
Bleed air properly using a reservoir in the filler hole. Run the car through a couple of thermostat openings. A heap of air will make its way out. Alternatively, use a vacuum filler that connects to an air compressor. They sucjk all the air out of the system and introduce coolant without letting air in.

The little screw thing won't do that so well.

 

[mirrabucca]

Have you checked the actual engine temperature via the "mode and up" buttons? (Engineer mode). Then you are seeing the actual temperature the ECU is seeing.
Just in case there's a fault in the dash somewhere. (The check engine light IS right under the temperature gauge...)