i have replace the temp sensor and the fan relay but still the fan doesnt come on
my car overheats at idle not sure why on 1996 Geo Prizm
It could have a stuck closed thermostat not allowing coolant to flow to the radiator from the engine, feel the coolant hoses to the radiator when the engine indicates it is getting hot on the temperature gauge.It the hose is cold coming from the thermostat to the radiator the t/stat is bad. After that you would need a wiring diagram for your car to start tracing wiring and fuses. There is a company that independent auto repair shops get their information from, this same information is available inexpensively for people that work on their own cars.. The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online
but why the temp keep going higher and the fan not coming on ?
ck pwr to your fan motor maybe the fan motor is burn't up.take a 12v source and jump the fan motor to see if motor is bad