2003 S40 1.9 All symptoms point to temp control sensor. but not.
 

Hi. wondering if anyone can help. 1- cooling fan works but does not turn on when hot. 2- cooling fan sometimes turns on when cold just when key is on and then for a little while. 3- engine surges. 4- will not restart or very hard to start after engine running for a while. Temperature gauge erratic. jumps to hot for a second or two when cold then registers cold when engine is hot.

Cooling system is full. Thermostat is opening. Changed the temp control sensor. Fans work when A/C turned on. No check engine light coming on and no codes.checked plug connectors.
I dont where to go next...Anybody???

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