Hi everybody. I have a 2001 Accord V6 with 142K miles on it. It has a new tranny with 12k miles and the radiator is about 4 years old. Last weekend while I was driving the temp gauge all of a sudden shot up to H really quickly. I immediately pulled over and checked the coolant reservoir and it was bone dry. Also, there was a significant amount of coolant dripping out from underneath the car. I added coolant to the radiator as well as the reservoir and as I was driving home I had to keep the heat on all the way to keep the temp down. The temp guage stayed at H until I got to 40 - 50 mph and then it would drop down to normal but as soon as I turned off the heat or dropped below 40 mph it would shoot back up to H. When I got home I installed a new thermostat and gasket an I let it sit overnight. The next morning everything looked OK but as soon as the car warmed up it started overheating again. I checked the reservoir and most of the coolant was gone. Please help! Thanks.

Update: Let the car idle an overheat with the AC (heater) off. Turned the car off but left the ignition on. I noticed that neither fan turned on when the temp was in the red and they did not automatically turn on when I turned the car off. I then started the car and turned on the heater and both fans turned on. I felt both radiator hoses and they seemed to be the same temperature (hot). Also, there was about 2 cups of water and coolant that had leaked out near the drivers side front tire. It seems to only leak coolant after the car has been turned off. Could it be the water pump?

 

i am having the exact same similar problem as you are having. i also noticed the leak on the drivers side and was thinking of replacing the thermostat along with the radiator hoses. were you able to resolve your problem? Thanks,

 

Good to know. Can't you see EXACTLY where it's dripping from??

 

its hard to tell but it seems like it might be dripping from where the radiator hoses go into the engine. maybe thermostat issue? Also, it usually drips on the drivers side in small amounts when the car is turned off. it is not a continuous leak. very puzzling problem and very similar to the original poster. any insight is appreciated. Thanks,

 

to be more specific on the dripping, i would drive the car for a while and then when i turn it off thats when it leaks water. recently its been leaking while the car is warmed up in smaller amounts. if the car is off and i fill the radiator, the car would not leak at all.

 

1. Find the source of your leak. Fill w/coolant and let the car idle and overheat in the driveway so you can trace down exactly where it is leaking from. There will always be one spot it is coming from, use a mirror on a stick if you can't see because of wires/hoses in your way. If it is only expelling coolant from the expansion tank, see step 2.
2. Check the fan switch (jfreidel88, this sound like your problem). There should be a switch in the bottom of the radiator that turns the fans on when the coolant reaches a certain temp. If this switch is bad you the fans will only come on when the engine is turned off (the ECU will turn the fans on after the engine is off to if the temp is too high regardless of the switch). To check it; unplug the connector and jump the terminals on the connector (cut a short wire and touch it to both contacts on the connector). If the fans turn on when jumped, but do not when plugged into the switch when the engine running and hot, then that switch is bad. Drain the radiator and replace that switch and you should be good to go.

 

it ended up being one of the shorter thinner radiator hoses that was busted. I changed that out and the car is working great. thanks for everyones input.