91 A/C not cycling/freezing up | Ford Explorer Forums - Serious Explorations

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91 A/C not cycling/freezing up


Elite Explorer
October 19, 1999
Reaction score
City, State
Cape Coral, FL
Year, Model & Trim Level
'91 EB
The A/C blows cold for a while then blows cool. (if that makes sense) The compressor is not cycling frequently so I don't think I have a freon leak. Compressor, evaporator and most hoses are new. In fact it appears the compressor is just staying on. When I turn off the truck a big puddle of clean water forms underneath. And of course the A/C is cold again.

Looks like a case where the AC coils are freezing up and not defrosting. Somewhere I recall there is a sensor that controls the cycling/defrost of the AC circuit.


1. Where is said sensor.
2. Is it cheap and worth a DIY even if it is not the culprit.
3. Anyone run into something similar?


One of the door control hoses cracked in half and fell down out of the way (out of sight). Guy at Autozone gave me 3" of vac. tube for free and was fixed in 2 min. Can't believe I missed the obvious...

Cleaned up the slight rough idle too. Gotta love vac.