Cleaning evaporator and heater core

[Bill R.]

spray cleaners are designed for. When the dust ,dirt, mold etc mixes with the moisture thats always condensed on the evaporator it forms a gunk thats pretty hard to get off without the spray cleaners..You can get access to it by removing the glovebox and taking off the cover where the sword would normallly live, I don't think you have a sword but the cover should be there.

I will try to get me some before I button it up. I already did pretty good so far with a stiff nylon bristle brush and a vacuum cleaner. If the heater core was nearly blocked and filthy, I wonder how the evaporator looks. That looks like a lot of work to get after it, so I will hope for the best right now. So far, in the summer, I have measure about a 5 degree temp difference between the left and right side vents, the left being warmer. I replaced the electonic heater valve with new without any change in results last summer. Wonder if this blockage had anything to do with it. It never did blow the volume of air like my E32 does (replaced the evaporator 7 years ago because of leak, not clogged). I did happen to see a really clogged evaporator from a car owned by a dog fanatic that obviously shedded lots of fur in the car.

[KeithW '91 535i]

Thanks again, Bill R.
I found the BG product via special order at my local NAPA store in Scottsdale. It costs $40.00. NAPA says their BG products are really very good. Fuel injection cleaner is the only BG item they stock. I did order the Frigi-clean (part #709 from BG) and it will be at NAPA within 24 hours. Thanks for the tip on reaching the evaporator, too. I will do that and can't wait for summer (the only good reason I have) to see if there is a gain in a/c performance. Have a great day! Keith

spray cleaners are designed for. When the dust ,dirt, mold etc mixes with the moisture thats always condensed on the evaporator it forms a gunk thats pretty hard to get off without the spray cleaners..You can get access to it by removing the glovebox and taking off the cover where the sword would normallly live, I don't think you have a sword but the cover should be there.