I have recently noticed my 80ZX having an overheat problem, first indications of this problem was the temperature started creeping to between half way and 270f during stop and go traffic. Lately I've notice a knock, (like low octane gas) noise when I get down on the accelerator, and just yesterday the temp shot up to 270f in stop and go traffic. It does go lower when air starts getting through it at speed. Looking for places to start trouble shooting myself before I spend big bucks taking it in!! Anyone got any easy fixes????