Re: 5KCSTQ Fan Issues

["Richard Haroutunian" <Richard_Haroutunian@inso.com>]

Wallace:

I think you're right.  I did another test (SJM's test) this morning where
you idle the car until the second fan kicks on- and then quickly shut the
car down.  The low speed fan and pump are then supposed to kick on within 5
min. of the car being shut off.

On my car, the pump kicks on, but the low speed fan does not.

So, I have a rad fan that only appears to be working on one speed.  I think
that the increase in loudness is due to the fact that the fan only works on
the 'jet engine' speed-- and the 1st and 2nd speeds aren't working at all.
I'm not sure if this is possible, but the fan is definitely much louder
than usual.

My question now is whether or not the car can wait until next week to be
fixed-- or should I not even chance it and drop it off for 'emergency
service.  I'm pretty sure it can only be one of two things: (1) the
3-pronged radiator plug that controls the 3-speeds of the fan is
'burnt-out' and therefore the fan only has 1 speed-- FAST...  or, (2) the
relay for the low speed fan ONLY (under the dash) isn't working.

It can't be the relay under the hood that controls both the pump and the
low speed fan, because the pump is working fine.  It also can't be the
'after-run' sending unit on the cylinder head, because the pump runs fine.

Does this logic seem to work for you?  If not, what else could it be?

Is it possible for the rad fan to operate on one speed-- jet engine-- vs.
the second speed it is normally supposed to operate at when the car is
running?  Is it smart enough to realize that speeds 1 and 2 aren't working-
and that the only way to cool the engine is with the speed that still works
(jet engine)?  I guess this would explain the fan being louder than usual.


TIA for any help!

Richard
87 5KCSTQ
85 4KSQ
82 VW Cabriolet