Sounds like your cooling fans are not coming on at the proper time in
non-A/C mode intermittently. Remember, when you turn on the A/C... the
cooling fan(s) come on whenever the compressor is engaged. Maybe the
switch you boiled is intermittent. I would change that first.

Professor
www.telstar-electronics.com

Sam Nickaby wrote:
> The car is overheating (needle points to red line) idling in traffic. When I turn on
> the AC, the temp is fine. When I turn ignition off the condenser fan kicks in. I then
> drive home and remove the bleed hole and find no trapped air (temp dial is set to
> HOT.) I then remove the (92-96 C) fan switch. I jump the switch terminals with
> ignition on. The fan runs. I pot boil the switch connected to an ohmmeter. Right before
> the water begins to boil, the switch closes. I reinstall the switch, refill, bleed and
> allow the fan to come on twice, as instructed by the service manual. The car does
> not over heat anymore, confusing. What could cause this random overheating?
>
> Thanks