Date: Sat, 2 Sep 2000 08:26:14 -0700
Reply-To: Bill Davidson <wdavidson@THEGRID.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Bill Davidson <wdavidson@THEGRID.NET>
Subject: Re: testing temp 2 sensor?
Content-Type: text/plain; charset="iso-8859-1"
Ken...
The light bulb has been turned on !!
And now I see said the blind man :)
Thanks,
Bill
----- Original Message -----
From: "kenneth d lewis" <kdlewis@juno.com>
To: <wdavidson@THEGRID.NET>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, September 02, 2000 5:49 AM
Subject: Re: testing temp 2 sensor?
> Bill;
> This graph created a considerable amount of watch winding and
> head scratching for me too. The second half of the graph is actually a
> continuation of the first half but in an expanded view. If you look
> carefully the two graphs are numerically continuous. Use the left hand
> ohm values for the left graph and the right hand values for the right
> graph. You will see where the curve crosses the 50ºC line from the left
> the resistance is about 800+/-100 ohms. Notice also the resistance is
> about the same crossing the 50ºC line into the graph on the right using
> the values on the right. It is a lot easier to read the graph on the
> right at these lower values.
> If you are going to ohm out the sensors I recommend you only use
> a digital meter. A quick and easy check is to compare the resistances of
> the TEMPII and TEMPI sensors after the bus has sat overnite so their
> temperatures equalize. Their values should be nearly equal. It IS
> possible to pass this test and there still be a problem at other
> temperatures.
> Our 85 ran fine during warm weather but when really cold temps
> arrived it would not start. The TEMPII sensor was reporting a warm engine
> hence the ECU was leaning out the mixture.
> To be absolutely sure, purchase a new one and test it at
> freezing, room temp and boiling temperatures. A spare is also a good
> idea. Our 85 is on her third TEMPII sensor.
>
> Drive Safely & Good Luck
> Ken Lewis <Kernersville,NC>
> 86 VW crewcab;60 356B Coupe
> --------------------------------------------------
>
> On Sat, 2 Sep 2000 02:20:25 -0700 Bill Davidson <wdavidson@THEGRID.NET>
> writes:
> >On page 24.45 the Bentley shows a graph that plots ohms vs
> >temperature...
> >
> >I've been assuming that the left side of the graph is for the temp 1
> >sensor
> >and that the right side of the graph is for the temp 2 sensor....
> >
> >But it does occur to me that at 50 deg C (the dividing line between
> >left and
> >right sides of the graph) the sensor(s) could conceivably have a
> >discontinuous relationship between ohms and temperature, i.e.: both
> >sides of
> >the graph would apply to both sensors??? So which is it?
> >
> >Thanks,
> >Bill
>
> ________________________________________________________________
> YOU'RE PAYING TOO MUCH FOR THE INTERNET!
> Juno now offers FREE Internet Access!
> Try it today - there's no risk! For your FREE software, visit:
> http://dl.www.juno.com/get/tagj.
>
|