Date: Thu, 7 May 2009 07:38:29 -0700
Reply-To: Rocket J Squirrel <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Rocket J Squirrel <camping.elliott@GMAIL.COM>
Subject: Re: O2 sensor transition time
In-Reply-To: <96c89c360905070556l3f4e5d97td9b65e73c4e8ed31@mail.gmail.com>
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That's way slower than on my 1.9L.
--
Mike "Rocket J Squirrel" Elliott
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
Bend, OR
KG6RCR
On 5/7/2009 5:56 AM Larry Alofs wrote:
> I thought that David WAS the original poster. :-)
>
> My answer:
> The one I have watched recently took about 2 sec to go from low
> voltage to high and vice-versa, at idle. This may not be typical. I
> believe it is the original VW sensor in my '91 GL with about 160k
> miles presently connected to a Subie EJ22.
>
> Larry A.
>
>
> On Wed, May 6, 2009 at 10:08 PM, Scott Daniel - Turbovans
> <scottdaniel@turbovans.com> wrote:
>> very good.
>> what is your answer then, to the poster's question ?
>>
>>
>> ----- Original Message -----
>> From: "David Beierl" <dbeierl@attglobal.net>
>> To: "Scott Daniel - Turbovans" <scottdaniel@turbovans.com>
>> Cc: <vanagon@GERRY.VANAGON.COM>
>> Sent: Wednesday, May 06, 2009 7:11 PM
>> Subject: Re: O2 sensor transition time
>>
>>
>>> At 09:39 PM 5/6/2009, Scott Daniel - Turbovans wrote:
>>>> a new Bosch, and using a digital volt meter......
>>>> the voltage was going from about .2 to .8 volts very, very fast.
>>>> Like several swings in voltage change or range, per second.
>>>> I had never bothered to check a new one much.....and boy, did this one
>>>> change voltages fast.
>>> Hi Scott -- unfortunately, with a digital meter of the usual type it's
>>> very tough to see what's really going on, only that something is. This is
>>> because most digital meters use a technique called "dual-slope
>>> integration" to develop the reading. They typically generate a new
>>> reading about 2-3 times a second, and use a significant fraction of that
>>> time to sample the input signal; so when the input is changing the results
>>> appear somewhat random. The ideal way to measure is with a scope, but an
>>> LED bar-graph display driven by an LM3914 chip, like Ken's little gadget,
>>> is a very good alternative for this particular signal.
>>>
>>> Cheers,
>>>
>>>
>>> --
>>> David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
>>> '89 Po' White Star "Scamp"
>
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