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Subject:Re: '86 F.I. probs continued.
From:Darrell Boehler
Date:Tue, 4 Aug 1998 08:47:17 -0500

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Hi Eric,
    After traveling around with a digitool attached to my 86 for over a
month I think I can help you determine if your temp 2 sensor is good.  One
wire to the sensor is  brown with a white trace. It supplies a ground from
the ECU to the sensor. The  other wire is white. The ECU puts a voltage of
5.2 volts on the white wire (with no load) when the sensor is disconnected.
The sensor  has much resistance when the engine is cold and pull the voltage
from 5.2 to about 1.5 volts if it is 70 degrees F.  If it were below zero
degrees F the voltage would be about 4 volts.  As the engine warms the
resistance of temp2 decreases and the voltage on the white wire digifant ECU
pin 10 will decrease to less than 0.1v the digifant tool shows mine runs at
0.02 volts with a hot engine.
    I have grounded the temp2  wire  on air cooled engines to prove a temp2
sensor was good or bad (I had no tool to attach to the air cooled) .
Grounding the white wire  should work just as well on an 86.  Do this after
it has warmed up a bit if it runs normal bad temp2 or brown wire  if not ok
look for a broken white wire from  temp2 to ecu pin 10.  Actually and maybe
easier if you bridge ( short the contacts)  the temp2 connector and all is
good you have a bad sensor. Good luck.

Darrell

-----Original Message-----
From: Eric Pickering <pickering.14@OSU.EDU>
To: Vanagon@VANAGON.COM <Vanagon@VANAGON.COM>
Date: Tuesday, August 04, 1998 6:51 AM
Subject: '86 F.I. probs continued.

>OK, after many suggestions (O2 sensor, thermostats, other wiring, etc) and
>much checking (O2 seems OK) the thermostat temp sensor (the blue one on the
>front left, heat sens #II-?) may be the culprit.  When the engine get warm
>and starts running crappy I unplug it and it starts to run just peachy.
>Now, it runs much better and doesn't stall out but it won't drive with much
>of a load (slight up hill).  So, do I just replace this sensor or might it
>yet be something else that I haven't investigated that the new info points
>to?  PLease respond ASAP and thanks to all who have.
>
>Eric
>