Date:         Wed, 13 Apr 94 16:32:44 CDT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Joel Walker <JWALKER@ua1vm.ua.edu>
Subject:      Re: Vanagon idle hunting

>dealer could tell me was "everything is fine".

yeah. that's what they kept telling me, too!!!

>'87 models come with the Digifant system, Right?  .  Looks as if the coolant
> temp sensor I need to relace is mounted right under the thermostat housing
> and can be easily removed from above.  Apparently you remove the retaining
> clip, slide out the old/in the new, and you're done.  I suppose some coolant
> loss is inevitable, so I should release any residual cooling system
> pressure first. There must be a rubber seal--should it be replaced too?

last thing first!! YES, by all means get a new o-ring. :)

ok. the Digifant system was used on ALL 1986-1991 vanagons (on the 2.1 liter
engine). on the 1983-1985 1.9 liter engines, they called it Digijet. it's
supposed to be pretty much the same, but ...  it's also 'supposed' to be the
same as Bosch Motronic (on bmw's) but WITHOUT the knock sensor and timing
control. i don't know that for sure.

the sensor you want is the one on the left side of the thermostat (looking
from the rear of the car). the other sensor is the one for the coolant gauge.
i just removed the clip, disconnected the wiring connector, then you remove
a bigger clip (which locks the sensor in the pipe), and then the sensor will
slide/wiggle out. sometimes the o-ring does NOT come out with it, so you'll
have to stick your finger in there to get it. i wiped with an old t-shirt to
clean up any whatever than might have accumulated around the o-ring.

you WILL lose coolant, but not much if the car is level. i didn't do anything
special to the coolant tank or system about releasing pressure ... but i did
bleed the system afterward.

have the new sensor (with the new o-ring on it) ready so you can do this as
quickly as possible. you may have to wiggle the new one a bit to get it in
and you'll have to kinda push on it to put the big clip back in.

i recommend doing it from above. :) the first time i did it, i laid on my
back under the car (well ... it looked like it would be easier to get to
all the pieces). WRONG!! you get coolant all over you. from above is better.
trust me.  also be sure to let the car cool off a LOOOOONNNNNNNGGGGGGG time.
even four hours later, the coolant was rather warm! hot coolant is NOT fun.

also: when you disconnect the wiring harness connection, get it up and out of
the way (so the coolant coming out doesn't get it wet).  try to dry everything
off before you hook up the wiring again (check the connectors on the sensor
to be sure there is not any coolant in the little recesses).

and that's about it.  my sensor cost me $30 (i think) and the o-ring was about
$2.00. yeah, that's what i thought, too. maybe next time i'll go down to the
local hydraulic supply house and see if i can match an old one. :)

good luck.
joel