Over Heating at Idle

[NC300ZX]

Whenever the thermometer climbs above 85 degrees my 1993 300ZX convertable runs hot. The temperature gauge does not spike but it does move closer to the H end then it is to the middle.

This only occurs at idle or low speeds (stop and roll traffic). At highway or even city street speed the temperature returns to normal.

Has any one else experienced this condition?

[silpena]

i had this isue with my 240 it would heat up at idle and street cruising or high way it be stable. Also stop and go it would rise up then i give it some gas it go back down. sounds like you??? It could be your thermostat getting stuck or not opening up at operation or worst u have a blown head gasket not fully blown but maybe a slight crack in it near the water jacks. The pressure from the piston goes into the coolent system, doesn;t mix but put more pressure then it needs to operate so the thermostat can't operate right and all of it builds up then goes down. I check it out ifi were u. Open ur radiator cap (when cold) turn ur engine on and let it warm up and see if theres bubbles in there. YOu can burp it and see if that helps but if what i think is true then u'll see bubbles and thats means air getting into ur system. Your water pump is made to pump like at 25 psi adding over like 150 psi isnt gonna let function well. Check it out man see if that helps.