[Vwdiesel] Temp light blinking-engine cold !

[Sandy Cameron]

At 10:29 PM 28/01/05 -0400, you wrote:

>Problem is....when I revved it up to past 1500rpm (guessing, I have no tach)
>the temp light started
>blinking and the guage gradually (10 seconds ot so) went over to
>"hot".........

I think you said you changed some batt cables.

Grounds are funny on all volks's

If you have run a new fat ground cable from batt- to the block, you must
ensure you have a good bond between the batt- and the body as well,
otherwise strange things will happen.

The temp system operates by a thermistor located at the heater outlet at the
end of the head. On older cars it's a single wire, depending on the ground
integrity between the engine block and body. In 89 and upward, the sensors
were 2 wire, (IE they carried their own ground back to the instrument)
 Testing the temp circuit is easy. With the wire (yellow/red?) off the
sensor, the guage will not move. With the wire GROUNDED the guage will go
full scale.

It's possible you have accidentaly grounded it while wrestling with the
heater hose, which connects to the same outlet from the head that holds the
sensor.

But my bet is a poor ground bond between the body and the engine (which sits
on 3 rubber mounts)

The body ground tab. on the frame behind the battery (between the batt. and
the WW reservoir) must be bonded to the block of the engine.

The volks cable from there to the tranny will NOT be a good connection. In
the 86's, the engine end was often bolted to a rusty steel tab, in turn
bolted to the heavily oxidized aluminum tranny case, resulting in no
connection at all after a few years.
Remove all connections, clean thoroughly, wire brush, apply silicon grease,
wire brush the bolts too, and reassemble.

If using the original volks cable, ensure the cable in the crimped lugs has
not turned to brown dust. I would replace with new cable and soldered-on lugs.

Sandy