I have a 2003 honda accord. It over heats sometimes. When...


I have a 2003 honda accord. It over heats sometimes. When I turn on the heater it cools down. But, sometimes the heater blows cold air. Sometimes it needs water Mechanic's Assistant: Have you checked to make sure the [ther...

I have a 2003 honda accord. It over heats sometimes. When I turn on the heater it cools down. But, sometimes the heater blows cold air. Sometimes it needs water Mechanic's Assistant: Have you checked to make sure the [thermostat](/topics-thermostat-honda/) is working? What about the coolant level? Thermostat was changed and coolant level is good Mechanic's Assistant: Are you fixing your Accord yourself? What have you tried so far? Changing the thermostat. Yes. Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? Yes. So the car tends to overheat more when going up hill.

Automotive Expert
Hi! Welcome to JustAnswer. Thank you for contacting us for assistance with your vehicle. I'm Ron. I will be happy to assist you with your question. May I ask to whom I have the pleasure of speaking with today?

Angie
Automotive Expert
Hello Angie. Nice to see you today! I'm sorry to hear you are having this problem. I know this can be frustrating. Please give me one moment to type out some information for you. Sit tight one minute. I'll be right back!

I have a Honda that has a new thermostat. But it is still overheating sometimes. Mainly while waiting in a drive thru or going up hill. All I have to do is flick on the heater and it cools down immediately. But, sometimes the heater blows cold.Hello?
Automotive Expert
Thank you for holding Angie, The problem you are describing sounds very much like you have trapped air in the cooling system, the trapped air will also cause the heater to come and go with heat due to the air in the system, having tapped air will also cause the engine to overheat. The place to start here is to bleed the cooling system and the best way to bleed your 2003 Accord is with a vacuum bleeder. Doing it this way will remove 100% of the trapped air that usually ends up in the heater core. I have enclosed a video explaining how to do this type of bleed procedure. If you do not have the equipment to do this yourself, any good automotive shop can do this for you as well and usually charge less than an hour in labor. [https://www.youtube.com/watch?v=vwUHkee-ovw](https://www.youtube.com/watch?v=vwUHkee-ovw)

Oh good. So you don't think it is the [water pump](/topics-water-pump-honda/)?
Automotive Expert
If the water pump is not leaking then no, it's not likely a water pump. It's a good idea to have the cooling system pressure tested before you do the bleed procedure and that will tell you if in fact there are any external leaks as well.

Ok, how do I check if the water pump is leaking?I'm sorry, the only car I have worked on was a saab. A couple of them. Never worked on a honda.Actually, I think you have given me enough resources to figure it out. Thank you very much. Have a good day.
Automotive Expert
Usually, if it is you will see coolant dripping out of the bottom of the timing cover and the pressure test will add pressure to the cooling system, and that will tell you as well. If there are no leaks, the system will hold steady pressure.
Automotive Expert
You're very welcome, Angie! Glad I could be of some help today! I hope everything works out well for you! If there are any additional questions on this issue that should arise, please feel free to reply and ask! Have a great day

I am extremely impressed with Ron. I have used "Just Answer" in the past and have not had any success. Ron was informative and personable. Very happy with his responses.
Automotive Expert
Thank your Angie, very happy I could help you with this.

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