Coolant Odor inside my Mustang When Heat/Defroster is Turned On

Discussion in 'SN95 4.6L Mustang Tech' started by RED2001GT, Mar 13, 2007.

  1. This only happens when I first turn on the heat or defroster when my car is cold. I get an odor which smells like coolant. This coolant odor goes away after a few minutes (about 5 to 10 minutes) after the heating system starts to blow hot air into the car's cabin. I've noticed this odor only when I first start my car when my car is cold when I put the heat or defroster on just a few minutes after I warm my car up. The heat setting on the heater/defroster dial is always in the maximum hot position when I turn the heat/defroster on.
    I would like to know if it's normal to smell this particular coolant odor when I always turn my heat and defroster on?
    This is happening to my 2002 Mustang V6. I would think that the 4.6 Tech people in here might have a better idea about this problem than the V6 forums because the V6 forums are always dead. That's why I posted it in here.
  2. You have a leaking heater core. It is behind the dash and is quite a pain to change out.
  3. I didn't notice any coolant on the carpet or anywhere on the driver or passenger floor. Are you sure that it's leaking inside the car? Because if it is, I haven't seen any on the floor on the carpet. And like I said in my previous post, the coolant smell is not strong and it goes away after 5 to 10 minutes when the car warms up and hot air starts flowing inside the cabin. I only got 40,000 miles on my Mustang. What would cause the heater core to leak with such low mileage on it?
  4. It doesn't have to be much to get the smell. Could be minor for now but it will eventually get worse. The mileage really doesn't have anything to do with it. They can fail from age or just a faulty part.
  5. I purchased the 7 year/100,000 mile bumper to bumper Ford ESP extended warranty with my Mustang. I believe that I have a $50 deductible with the warranty. I have until January 2009 til the warranty runs out.
    Do you think that this problem will be covered under the warranty if it's the heater core? Will Ford fix it under the warranty for free if that's what the problem is? How much will it cost for parts and labor for Ford to fix it?

    Also, if I bring it to Ford, I am afraid that they might not smell the odor if the engine on my car is already warm. I've noticed that this coolant odor occurs only when the engine on my car is cold and after I start the car with a cold engine. The odor goes away after 5 to 10 minutes.
    So you really believe that it's a leaking heater core which is really causing this?
  6. Man...lucky you. Just take it to a dealer and have them diagnose it. I guarantee you if you tell them what you said here thay won't even think twice about doing the work. It will be covered.
  7. Mine did that one time and it was a weak stock hose clamp going to the heater core. It was sparying/dripping onto the little piece of foam insulation in between the core and firewall. When I turned the heater on I could smell the antifreeze. Fixed it and after it finally dryed up it stopped smelling bad. I'm glad it wasn't the core in my case good luck!
  8. If it is the heater core, thank your lucky stars you have the warranty. Worst job on these cars EVER in my opinion. If mine ever goes out again, I will pay someone to fix it.
  9. take it to the dealership and tell them exactly what you mentioned here that you only smell it when its cold, and they will let the car cool down and check it so it might be a while for them to diagnose it
  10. It's not an easy job but if you have a warrenty then no worries.
  11. How often are the people experiencing heater core failures changing the fluids? I have changed mine at least 7-8 times.
  12. My Heater core is going too then..
  13. mine just went last week :( I dont know if its a plug or hose but i hope it is...

    right now i just have it bypassed bc i live in texas (it was snowing here on saturday!!!)