Radiator fan stays on after engine shutoff

[ventureforth]

I have a 1.6NA '82 Rabbit.  Lately, when coming back home at night on my daily commute (about an hour), the radiator fan will blow for  about 20 seconds or so after I shut off the engine.  It has happened only a few times.  I make the trip 3-5 times a week, so I would think if it were normal it would happen more regularly.  I seem to recall the same thing happening on my '00 GTI, but never on my '03 TDI.

Anyway, just wanted to be sure this was normal (or not), to put my mind at ease (or not).

Thanks

[Quantum TD]

Afterrun is completely normal. But, generally the fans should only run for about 0-5 minutes max. Anything after that is need for concern. Long afterruns usually are indicative of a bad switch that keeps contact too long.

But 20 seconds is totally normal. If it stays on longer than 4 minutes, then start to worry.

Finally, it's probably a good idea to have a spare fan switch with you at all times (I do. It is a VW afterall)

[ventureforth]

Yeah.  Single speed.  But since it only goes for a 20 - 30 seconds, maybe a minute, at most, I guess I'm good.  Curious, though, how identical driving conditions, durations, temps, etc., sometimes result in afterrun and sometimes do not.  Could that indicate something else going on?

[Baron VonZeppelin]

Curious, though, how identical driving conditions, durations, temps, etc., sometimes result in afterrun and sometimes do not.

Theres always some variants somewhere. A slower driver ahead, a longer wait at a stoplight / stop sign. More time spent behind other cars versus being lead car and getting best air.

Sometimes your fan probably cycles shortly before you arrive home, and doesn't need an after-run. I doubt it cycles the exact same number of times at the exact same distance points everytime on every trip.

If you get a good accurate auxillary gauge, you'll notice coolant temp rises some when engine is shut off, versus the steady running temp it had while the coolant was circulating.

A short after-run is actually a pretty good sign to see once in a while - it lets you know the fan system is operating correctly and its looking after your car.

Some longer after-runs happening frequently would be when you'd want to start some diagnostics.

[Smokey Eddy]

I wish my fan came on more often. I never get any high temps on normal drives but it's always re-assuring to see it actually pushing some air!