I have a Nissan 300zx Twin Turbo Coupe. It has approx 120,000 Miles. I moved to the Phoenix area where the weathure as you know is extremely hot!! Temperatures are around the 115 degree range every day. My car has started to get hot, the guage normally will stay right in the middle and now it goes all the way up to the "H". When I turn the air cond. off, it goes back down to normal. But when I turn it back on it will get hot again. I do not allow my car to get to hot as I will either pull over and let it cool or turn the air off. It doesn't spew water or leak for that matter anywhere. I have checked the coolant several times and didn't need coolant. My elec fan runs and the mechanical fan clutch seems to be functioning properly. Any suggestions??

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1993 Nissan 300zx 3.0 twin turbo

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