Celica Gt High Idle Revs

[Blue2.0GT]

Hi All,

Just lately my Celica GT (1995) has been idling at unusually high revs, around 1800rpm. It stays at this level and perhaps drops down to 1400 even after say a 15 mile journey.

This problem also seemed to coincide with me changing the water temparature sensor (the one that links to the temperature gauge on the dash) and coolant. The previous sensor was knackered (always reading max temperature when starting the car from cold). but now with the new sensor after a 15 mile journey, the temperature sensor reads fairly low, whereas before the old sensor wore out, after such a journey it would read at leat a third up on the temperature range.

I had a look around other forums and someone mentioned that a faulty termostat could lead to high revs, but if this was a problem would this lead to the heaters in the car not working? They work fine right now.

Any feedback would be well received!

Thanks

Peter