I've got a curious overheating issue that I wonder if anyone could shed any light on...
Just had this 2001 147 TS 2.0 for a few weeks now, I love it to bits (I've posted a rambling intro post about it!) The car was sat for a long time approx 5 months on the previous owner's drive unused, its done 72,000 miles.
In the last week I've had done:
- new cambelt
- new water pump
- service, oil and filter, coolant flush
- cleaned all relay connections and sensor connections
I've had it on my local garage diagnostic and used my own reader and I'm getting no fault codes. The problem occured before the cambelt change and is still continuing after.
Here's my problem, after the engine warms up to 90, it'll then go up to 110 - 125ish and stay there for a bit, the high speed fan kicks in doing its alarming jet engine impression, and then it drops back to 90 after a few miles. My Torque OBD2 app says the actual engine temp is going from 83 to around 117. Being an aluminium head, I'm not sure I like this occasional overheating!
I did at first wonder whether it was the low speed fan not kicking in, but I've done the fan resistor test and all appears fine. My thermostat appears to work, the top hose warms up slowly with the engine getting up to temp.
Local garage says the system is pressurising, the top hose is too hard under the extra pressure, and the engine is getting too hot. They've bled the system and it still happens. It only really happens after start up and then very intermittently after that. Heater has a mind of its own too, keeps kicking in unexpectedly, even from the "OFF" position. Rad looks OK and garage confirm this too.
Has anyone had an experience with a thermostat sticking shut? Usually they stick open, lowering the temp. Wondering whether to whip it off, get a new temp sender at the same time...
Any thoughts greatly received, thanks everyone