My 1990 Acura Integra's fan (AC I think) continues to run hours or days after it's turned off. Of course, often the battery is dead as a result. Sometimes if I put the key in the ignition it stops. Sometimes, if I turn the key all the way to the right without cranking, it stops. Then if I turn it one click to the left it turns back on. I understand continuing to run for 30 minutes might be normal, but not for hours, or even the next day.
Its probably a faulty wire that is not getting a signal to the fan to shut off. Very strange. Doesn't seem like something you would be able to take care of yourself.
check the fan relay
the thermo switch is probably screwed replace and it should be fine
those late 80's early 90's hondas were equipped with a fan timer module. As soon as you shut off, if the engine was above X temp then the timer would run the fan for about 20 min after shut off. The problem however, was a burnt resistor sometimes and the fan would run continuously until the battery was dead. I know these are on the accords and preludes, and have repaired many of them, but dont know if they are equipped on the acura models. But i wouldnt be surprised if they are. Thats what your problem sounds like.
check your fan relay i had the same problem on my 95 integra ls fan ran all night and killed my battery had to jump my car and took it to a local shop that said it was the relay and fixed it within a couple of hours.
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