Overheating when car not moving

[ajc59]

I have a 1990 Park, runs great, travel 1300 miles per week, 180,000 miles on clock not problems except when I am in slow traffic I have to turn off engine or I overheat, can u help.

Thanks

[deadring]

well check if your radiator fans start when the cars gets hot for starters... then check the fuses..

in my opinion they don't

Deadring

[yogi_123rd]

Cooling fan info:

It consists of a temperature switch mounted behind the throttle body and in the intake to tell the ECM of a hot condition. The fans should be coming on around the 195-205 degrees range. It also has two relays located on the front driver side fender wall for the ECM to turn on the fans. One relay is for the low speed fan circuit used when the AC is turned on. The other relay is for the high speed circuit used when the ECM has detected a hot condition from the temperature switch. There is also a fuse for the cooling fan motor circuit.

To test:
1. Turn on the AC - your fans should come on at low speed. This verifies that the low speed relay is good.
if they don't come on, check the fuse or the motor itself.
2. If they do come on, now swap the relays. Try the AC test again. This will verify if the second relay is good.
If they don't come on - replace the bad relay
If they do come on, the temperature switch is most likely bad or there is a wiring problem somewhere.

[HotZ28]

If the fuses and relays are ok, take the wire off of the CTS and ground it to the engine. If the fan runs, you have a bad CTS, if not, it could be the fan motor. If you have fans running as normal and it is still overheating, it could be the thermostat, waterpump, restricted radiator flow on the inside or full of bugs on the outside.