2004 Honda Civic LX sedan 60,300 miles, used certified vehicle bought from howard cooper dealership in ann arbor mi. Engine did overheat at idle, 1/2 quart of coolant spilled on the floor of my garage. Coolant levels were topped after event, at radiator and bottle with 1/'2 qt of coolant. Vehicle was inspected at dealership, cylinder head gasket damaged, perhaps head damaged as well. Dealership was unable to tell me what was the cause of this event. Sufficient coolant was present at failure. Cause of overheat unknown. Was it the thermostat, the water pump, the cooling fan.." no service light or dummy overheat light ever came on. No BCM history codes appear to exist related to overheating according to the dealership. It is strange that a car can cook itself just like that, with coolant in it. I have done extensive web research and I find several complaints of similar related cooling system mishaps, on Honda Civics. My personal opinion is that this deserves some investigation. I find it odd that no definite answers are offered by the dealer on what went wrong. No history codes? is there a diagnostic fault signal from the temperature sensor, fan motor, water pump etc to the BCM" will (should) such signals set a code? very strange. I was being charged $1400 for the repair, but there is a chance that the warranty might pick up the cost. I don't know this for sure yet since analysis of parts is been done at the dealership. I am sorry, excuse me but I smell a rat here. It was like pulling teeth to get the dealer to look deeper into this matter. I had to write a letter to the general manager of this dealership to get some real attention on this. Come on, there is something wrong here. Updated 02/01/10.

- Ann Arbor, MI, USA