Radiator leak and heater problem all solved in one…

[1995 540i]

Hey bimmer nuts, so a few months back I was having problems with losing coolant, had my expansion tank replaced and still had a small coolant leak, well just last week I had my 1995 540i in the shop and turns out I had 3 small holes in my radiator. I went ahead and replaced it and when driving it home fig. I would try and turn the heat on and see if I was still getting fog mist. (For the past 2 years ive had my leak I have not been able to use my heater...) To my astonishment, my heat now works fine and I won’t be needing a new heater core after all. I just don’t see how a radiator leak could have caused my heater core to spit out fog mist but hey im not complaining!! Just wanted to touch base with you all and let you know I had 2 problems now fixed. Later sometime this summer I will be due for timing replacement as well as transmission fluid change, I wana get those 2 done before I hit the 100k mile mark….crazy

[bimmer nut]

Wow, kinda freaky solution for mist in the cabin, but as long as it worked, be happy.

[genphreak]

Maybe the mist wasn't from the heater core as some people have experienced.

Just guessing:

Was it steamy coolant from the engine bay coming through? That would inidicate your car has no cabin filter installed (ie its missing). Probably needs replacing anyhow given the coolant flow. Some people can smell coolant, others are oblivious, but a good filter probably removes the odours.

Unless the steam in the blower intake provides a humid enough air stream to the blower- and it's cold enough outside to the condense on the inside of your windscreen.

[1995 540i]

perhaps that was the problem, I will be looking into getin a new cabin filter (the one that is inside near the glove box) im going to replace it soon, and yes i do smell some coolant now when the heater works, honestly i can live with it, its not that bad and i no longer have fog blowing out, it was def. fog coolant like steam it was bad, now just hot air with a little smell so im happy~~

[Tiger]

I thought my car had the same heater core problem... turns out it was not... it was the octopus-like hose that attached to the coolant reservoir that was leaking... smell bad in the car.

Unbolt the reservoir and examine the hoses.

[genphreak]

The poisonous Octopus that occupies an BMW i6 seldom gets changed...

They often get pinholes and/or contract leprosy.

It's a wear item that should be done along with all the other cooling system hoses and wear items every 80,000km if you want reliability.