96 Continental overheats at red light

I have replaced both fans, thermostat, burped the system, replaced top hose. Car cools normally on highway until I have to slow to a crawl or stop for 2 or more minutes. Turning the AC off and turning heater on lowers the temp. In my driveway I started from overnight; let it warm up until a fan came on; then I turned on the AC; another fan came on for a while but then turned off. What do I do to fix it? I've spent $650.00 so far and it continues doing the same thing. It does NOT lose any coolant (only once when it boiled over....then it was properly burped after replacing the fans) Could it be relays and where are they? Thank you!

My guess, external fins on radiator clogged or internal clogged. Original radiator?

You could try a new cap.

Thanks, will look into it, although the overheating is just random, not continual.

Thanks, will look into it, although the overheating is just random, not continual. The new cap did not help. I noticed the high speed on the fans do not come on....any suggestions? Thank you to eveyone.