Hi,

I have lurked here quite a bit, but have never joined in. Well, my 97 Passport/Rodeo is giving me some trouble and I''''''''m hopeful someone here can help diagnose it.

It was down in the low ''''''''20s a week or so ago, and when I turned on the heater/defroster (A/C was on to de-humidify), the windows almost immediately fogged up and I could smell what I think is coolant.

Originally I thought it might be the A/C, but I''''''''m almost sure that it''''''''s working. Now, I''''''''m wondering if the heater core has a leak. The widows fog quickest when the engine is warm and I turn the heater control to "hot". It doesn''''''''t matter if the A/C is on or not. The problem is that I can''''''''t detect a leak anywhere. The coolant level does not seem to be dropping and there is no leak in the passenger compartment. Is there a drain for the heater core housing? Even if there is, it would seem to me that the coolant level would drop or that I''''''''d see a tell-tale sign of a leak.

Any ideas?

Edited by: mdatlanta

 

I had the same problem in my 92 3.1v6 until the heater core got a major leak and puked coolant all over the front passenger area footwell. You have a small leak on the top of the heater core, hence the fogging up of windows etc. and no visible liquid leaks at this time. Unfortunately you need a new heater core. I tried a cooling system leak stop product and it didnt work, I think because the leak has to be submerged in coolant for it to work.


Hope this is helpful,


Lefty249 Guy