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Now ive searched long and hard for answers but I couldnt seem to find anyone that had the over heating problem with no air conditioning which worked fine last summer. For starters the car is a 2005 1.7L with 175000 KMS on it the over heating started randomly in the winter and the heat would also only work sometimes. I had took it in to get the head gasket checked and mechanic said it was fine. New thermostat installed did not help. Now im not sure if the air conditioning not working anymore has anything to do with the over heating and the heat not working? Now to the fans, when I turn on the AC the fan does not come on although the fans do seem to work just not all the time and even when they do come on the temp gauge still seems to rise. There is no coolant in the oil and no leaks in the rad. If anyone else has any input and if anyone could let me know were exactly the fan switch is figure I mine as well try changing it that would be great aswell I do not know when or if the coolant has ever been flushed in this car thanks for any help!!!!!

 
Rep Power: 233

Fan switch is on the thermostat housing. It's the only sensor on the housing.

Sounds like your waterpump may be bad. Jack up the front of the car, crawl under the driver's side and look up at the weep hole for the waterpump. If there is more than a couple of drops coming out then you need a new waterpump/timing belt. At 175000KMS it's past due for timing belt/waterpump anyways. If there's no water then it's not the pump.

EDIT: Fix the overheating and the A/C will probably come back. The ECM/PCM won't let the A/C come on if it's overheating or is too much strain on the engine (like in WOT [wide open throttle]).

 
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had this problem numerous times on these cars all ended up being a bad headgasket pushing exhaust gases into the cooling system, the air pockets cause loss of heat temporarily, spikes in the temperature gauge, coolant boiling into the overflow tank. a blown head gasket doesnt necessarily mean coolant in oil, it can be exhaust side externally which pumps exhaust gases into your cooling system causing slow coolant loss without any visible leak. best way to tell is with an exhaust sample probe by the radiator neck, if you pick up anything over 150 HC's head gasket is toast. also after you have the head removed take it to a machine shop to get resurfaced for these heads are prone to warpage

 
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never had access to internet for awhile thanks for the replys I had another question im still seeing spikes in the temp gauge quite often except for when im on the highway the car runs at perfect temps why is this? if it was the headgasket wouldnt i see overheating on the highway as well thanks!

 
Rep Power: 233

^^ Pressure and heat cause the gasket leak to seal temporarily until you get on surface roads where the pressure and heat aren't as intense, allowing the leak to open again.

You let a bad headgasket go too long and you're guaranteed a destroyed engine.