Hi everyone, I'm new to the forum. I have some questions about my car. I have a 2003 Holden vy acclaim. I have recently replaced alot of parts. Most recently the thermo stat, plugs and leads, air filter (switched to k&n) and the altenator. As of yesterday, my cars temperature sits where it always does, then as I drive around for a little while the temp goes up a little bit. Just below hot. Then if I stop anywhere, traffic lights etc, the temp drops back down to normal.... I also noticed last night that even though I had used my air-con in the car that day, when I used it last night, the temp gauge instantly hit overheat. Turned the air-con off and the temp dropped but this time it only dropped to just below redline.. My question is, what could cause this. Thermostat has been replaced, coolant was bled all done about a month ago... Etc etc Help pleaseeeee!