I have a 1986 Camaro IROC Z 305 TPI. I haven't any cooling problems lately, though I had a few in the passed. The radiator is 5 years old, the water pump and the cooling fan are 2 years old. As far as I can tell both work. However, today while I was sitting in traffic my car overheated. I pulled into a gas station and let it cool down for an hour while I got something to eat.
An hour later she started up with no problem, I drove on the highway with no problem and when I got to the front of the community she overhead again! There was a little bit of smoke from under my hood (Drivers side look like underneath the block is where it was coming from). Driving the last mile the car got hot and I parked it in my driveway and killed it. There was still smoke from under the hood, the coolant overflow tank was overflowed. I checked the dipstick ASAP with my welding gloves and the oil was the normal gold color.

The last time she overheated was 2 years ago and the cooling fan no longer worked. She's been fine since.

It's been 30 minutes, the car is still cooling in the driveway and the overflow tank is still overflown. Any ideas of what it could be?

 

Fan and fan relay would be the first things I would check

 

I replaced the relay and when I drove this morning the temp gauge read just above 220 in crawling traffic and in between 100 and 220 at 60 mph. (I'm assuming this gauge is accurate, it's the one gauge I haven't had to replace. Also before overheating started that's what the gauge normally read).

When I got to my destination, I popped the hood, the coolant was normal no overflowing no smoke. Everything seems fine.

The only thing is the fan isn't coming on when I turn the AC on. It use to but not it's not. My AC compressor has a hole in it and I plan to replace my compressor and accumulator soon but that shouldn't affect the fan should it? Either way it seems to come on in traffic.

 

Hi, I have the same "problem" and I'm digging the forum about different stuff around the cooling system. To keep in the subject here, I didn't find any photo of the relay location. I want to check this. I'd also like a way to test the switch (I think I found it but I,m not quite sure about that) as well and I now know how to test the fan itself (just turn the A/C on).
In my case it's a 92 Firebird 305 TBI (L03 I guess from the VIN).