My Car has been performing normally until I flushed out the Coolant in the Radiator and reservoir and replaced with Honda type 2 Coolant. My Car started overheating when in traffic. Stops overheating after I turn off the A/C. What could be wrong?

 

Personally, I would check over any fans on the front or rear of the radiator to make sure that are working properly. When you turn on the air conditioning on most cars, I believe that a fan will usually turn on to flow air over the condenser coils, so maybe one of the other fans isn't working. I'm not sure how many fans your car has, but per http://www.hondaautomotiveparts.com/...%29+%28TOYO%29 or http://www.hondaautomotiveparts.com/...29+%28DENSO%29 it looks like there are probably two ahead of the radiator. You may be able to hook up 12V directly to the fans to check them. I'm not sure how the circuit is setup to get power to the fans (like thermostat, ECU, relays etc.), but if the fans don't run when you hook up 12V directly to them, then that would show to me that they were bad. - Jim*** Actually forget everything I wrote above. I thought you wrote that the car stopped overheating when you turned the A/C on instead of off. The A/C will put some extra load on the cooling system, but if everything is in good shape, then it should be able to handle it. Does the car overheat on the freeway/expressway, or only when driving slowly? It sounds like the radiator is somewhat plugged up, so maybe you could try flushing and refilling it one more time. - Jim

 

Sounds like you got an air bubble in the system. Turn the temperature **** or control to full red to open the water valve. Idle the car and see if both fans turn on as the car attempts to just start to go past the normal operating temperature on the gauge. Both fans should be coming on.

 

Didn't state if you bleeded the system, bleed the system.