Date: Tue, 23 Aug 2011 14:01:21 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: O2-sensor voltage problems '84 1.9L -- Help needed
Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=original
hi,
would love to really understand ..
re
"Voltage from O2-cable coming from engine is +0.46 volts. "
'voltage from cable from engine' ..
what does that mean ?
there is no cable from the engine ..
there is the signal wire coming out of the oxygen sensor, which is screwed
into the exhaust pipe or cat, that's bolted to the engine.
is that what you mean ?
doesn't make sense though ..
because ECU is not in the picture with that measurement.
are you saying ..
you are measuring voltage on the signal wire that feeds the 02 signal to the
ecu ? Like measuring into the ecu for voltage with key on or engine running
?
It would never occur to me to do that.
on my own 87 Wolfsburg ..
just had a whole go-around with a burst hose ..
which caused a somewhat tired distributor cap to act up ...
and I have another coil on temporarily,
and she ran fine for 20 miles...then started acting up again ..
weak throttle response, and if I cycle the key off and back on quickly, even
in gear...then she runs fine for a while.
To get home without that happening,
I disconnected the oxygen sensor signal wire,. and she ran fine.
I doubt anti-frz harmed the 02 sensor..
and I have seen anti-frz play total havoc with electronic and electrical
components before ..
like rendered them unreliable from then on, once that hot juice sprayed on
them.
my plan at the moment is try another 02 sensor, since I have a couple of new
ones at hand..
and ...
before that, unplug ecu and measure resistance between 02 single wire and
it's coaxial shield ,...see if perhaps there is a short there.
Scott
----- Original Message -----
From: "John Lauterbach" <jhlauterbach@BELLSOUTH.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, August 23, 2011 6:31 AM
Subject: O2-sensor voltage problems '84 1.9L -- Help needed
> Here are the details. O2-sensor not connected. Voltage from O2-cable
> coming from engine is +0.46 volts. Again, O2-sensor is not connected.
> I have tried with two different ECUs and get same result.
>
> With engine off, resistance between O2-cable coming from engine and
> ground is 140K ohms. I have a spare FI cable assembly and get same
> resistance from that cable when a ECU is connected.
>
> If I connect O2-sensor as intended, engine runs rich and stalls.
>
> John
