T reg 1.6 focus. 90k on the clock.
Heading out the other day 3 miles from home temp gauge goes to max and an orange warning light comes on (looks a little like a cog or a splash with an exclamation mark in the middle). Dive to hard shoulder and stop. Temp gauge drops to about 3/4. Trundle along a little and pull off next to a ford main dealer.
Expansion tank is virtually empty...
Top it up and wait 30 mins. Start car. Leave it idling and after 5 mins or so temp gauge goes sky high again *but no more warning lights*. Pull into the main dealer and ask if anyone could have a quick look.
"Sorry, too busy this week". This was thurs. "We could have a look next wednesday. Book it in" :-(
Go sit in McDonalds and think about it. Go back to now cool car and check water again. Attempt to get it somewhere more helpfull than ford and during my trip across town it is fine. Since then I have done 400 miles without a problem.
I know the coolant level was fine the evening before it overheated as I checked it along with oil etc. I didn't remove the expansion tank lid so the chances of it being loose are slim. Never had any other problems with the car overheating before. Bit reluctant to rely on it at the moment though :(
Any ideas? The only suggestion that has been made so far is that the thermostat stock closed and the engine overheated and pushed the water out. This then became unstuck as it cooled and the problem went away. There was no sign of steam and no obvious sign of water leaking from anywhere. No sign of steam from exhaust either. about a litre of coolant vanished via a route that has fixed itself :-( Also, it seems a little odd that I got a warning light the first time but then not again (I guess it maybe that I was being a lot more carefull to ensure it didn't get quite so hot the second time and it never triggered).
Does the thermostat theory sound plausible?
Cheers!
Darren