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Hi there,

Today on the motorway something strange happened, on the way to Northampton from B'ham traffic was standstill as it is usually on mornings, my engine overheated, I didnt check the dash all i heard randomly was a beep and when i looked the tempreature needle was nearing 130C - i thought it was because i was stationary and air wasn't getting to the engine, so i carried on til the traffic thined out. I was going about 40mph and the needle kept creeping higher to the 130C mark, so i pulled over on the hard shoulder and i turned my car off for like 1 minute, I turned it back on and the needle was at 90C again. Surely it can't cool down in minutes can it.

Could this be an electrical problem?

Thermostat problem?

Im not sure... should i get it checked out? Do garages nowday charge for checking your car out? or replace the thermostat myself..

How far had you gone before it started climbing?

Thermostat could have stuck shut and opened after you stopped the engine. Did you check temperature of top and bottom hoses when you stopped?

Did the fan cut in? (it's a separate sender for the fan, on the rad - well it is on earlier cars - presume these are the same)

Problems with the temp sender that feeds the ECU result in an engine management light, so presume that's OK.

In this order:
I'd check the fan,
check the fan sender,
then if those are both OK, get a bottle of coolant and a new thermostat.
Check the new thermostat in a pan of water before fitting (dodgy ones seem plentiful!) empty the old coolant (don't let the neighbour's cat drink it!)
flush the engine and rad before re-filling. Mix the new coolant BEFORE putting it in the car.