overheating?

[masokotanga]

I have a 1991 300zx n/a with about 150k miles on it. Stuck in a Houston traffic jam the other day (with the air conditioner on) I noticed the car start to overheat a bit. As soon as I got going again, the temp went back down to normal. Fans don't work? Anyway, I'm wondering if the thermostat is screwing up, because when I start the car after its cooled completely off, the needles stays all the way down, and then basically pops up all the sudden to the normal running temp. But sometimes recently it's started to show the car overheating even without the AC on, just driving down the street. It never gets all the way up, just overheats slightly. Anyone know what the problem is here? Coolant seems fine. Maybe a slow leak? What am I dealing with?

[CrazedZ32Owner]

you may have a small leak in the rad. that you do not notice yet.... my old NA did the same thing... check your rad for any cracks/leaks

[Z32man]

If there are no leaks, that may be normal. It is normal for that gauge to be anywhere but the red spot. While idleing the fans may turn off because there is no need for them or going at very fast speeds. You will only have a problem if it goes into the red area.