leongsoon 8 Report post Posted August 17, 2012 Hi guys! Here I am with another problem again! I'm aware there's currently an active thread about aircon problems here but I reckon the symptoms are different enough to warrant a different thread. For the past 2 days my car has been displaying these symptoms: 1. Aircon is slow to engage or doesn't engage at all even though all the aircon switches and lights are on properly. At idle there is a regular clicking sound every 30 secs near where the compressor clutch is but it doesn't really engage until I apply throttle. Once I've driven the car for about 2 minutes the aircon will kick in. 2. When the aircon is running, the thermostat and radiator fan behaves normally, kicking in around the 90c mark. My car normally runs at the high 70s (75c above or 80c) to roughly 95c 3. When the aircon is not running (even if it is switched on), the radiator fan doesn't work, even when it is already way past the 90c mark. And this is where the problem is; the aircon stopped working an hour ago and the fan didn't kick in. The temperature gauge has almost reached max by the the time I turned the engine off. Any pointers on the problem is much appreciated Quote Share this post Link to post Share on other sites
Smaky 73 Report post Posted August 17, 2012 I would say there is 3 problems. Thermostat is shot, Temp sensor is faulty or your head gasket has just blown. And the aircon needs a regas as atm it is right on the lower pressure limit which is why it needs a little bit of a run first to warm up the system and allow the marginal increase of pressure to hold the switch nd therefore engage the clutch. Quote Share this post Link to post Share on other sites
leongsoon 8 Report post Posted August 17, 2012 You're right Smaky; I've been paying attention to the temperature since you first mentioned that my car's thermostat is shot a few weeks back, it really runs too cool around 70c and might be causing the high fuel consumption. Anyway, when I sent my car to the aircon guys they said that since the cooling fan has stopped working, the high engine bay temperature has caused extra high gas pressure in the aircon system, hence the pump keeps disengaging itself to avoid damage to the hoses, I'm not entirely sure if the heat soak has such a profound effect on the aircon, but the cooling fan didn't work when we connected it directly to the battery, so I paid to have them replace it with a new one. There isn't any leak in the aircon system and gas pressure is adequate. With the new fan the aircon is now working again and engine temperature is back at 70c constantly. The fan's high speed kicks in real soon after starting the car. I've yet to check if the fan will come on automatically around 90c with the aircon off. Head gasket should be fine for now; coolant is still clean and no cloud on dipstick, also no sudden change in coolant level, thankfully! How do I test if the thermostat itself is shot, or if some sensor is feeding it the wrong signals? Thanks Smaky! Quote Share this post Link to post Share on other sites
Bigdar 62 Report post Posted August 17, 2012 Just change it, they're cheap as chips anyway, and an easy replacement. It shouldn't sit at 70 I don't think. Smaky will prove me wrong I expect Mine used to sit at 70 because it was stuck open. Quote Share this post Link to post Share on other sites
Smaky 73 Report post Posted August 20, 2012 Like said, no point mincing around with the tstat, just swap it and rejoice in the fuel savings Quote Share this post Link to post Share on other sites
leongsoon 8 Report post Posted August 21, 2012 Haha, alright, will do that then, gotta wait a bit till next month; wallet's taken a really big beating this month T_T Quote Share this post Link to post Share on other sites
