1994 Cadillac Fleetwood engine check light comes on when I drive at low speeds(25 to 40 mph) for any distance (3 to 8 miles) both fans come on and will not shut off until I turn car off, wait a few seconds for it to reset and then start the car. This does not happen in stop and go driving such as red lights, just when I drive at low speeds. The engine is not getting hot. I think it is a sensore malfunction. But which one?

I think the engine temp sensor is bad as well as the Tstat not working (stuck open)

do a search for trouble codes you'll find out how to pull you codes through the climate control. post the codes we'll let you know what they are...