Heater blows cold air, but the air conditioner works great.
What is your question?
The heater in my Honda does not blow hot air , and it overheats when driving up hills and on the freeway but it will idle without overheating for as long as I want, I have replaced the thermostat, I can not see any water leaks but it is losing coolant, I don't have any water in the car were you would have it if the heater core was bad, I was looking at the heater control valve and it doesn't seem to move from the position it's in but I don't know for sure the 2 hoses going to the heater core feel warm one might be cooler than the other but it's hard to tell cause there pretty close to the same temp.And also when I turn on the defrost the air conditioner light won't turn off, I don't know if this is normal or not.
What makes this problem better or worse?
It's worse when driving for long periods of time.
How long has your 2002 Honda Civic had this problem?
RepairPal Certified shops can diagnose and repair your 2002 Honda Civic. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Hello, you'll really need to get your engine tested for the cause of overheating. An engine thermostat that is not opening when it should is a possible cause. Repeated overheating can cause an a now internal engine coolant leak that creates overheating that comes and goes in certain conditions -- it's too hard to tell without performing hands on testing, checking for hydrocarbons in your cooling system, checking the coolant temperature and if the thermostat opens and checking for air flow through the radiator, for example.
Your air conditioner light should operate with the defroster, as the air conditioning system is used to dehumidify the interior at temperatures above freezing.
I'm sorry to say - you just need to have some professional hands on your vehicle.
Use this link to find some shops near you that can help with your concern:
www.repairpal.com/repair-shops
