Date: Sat, 15 Jan 2000 10:36:11 EST
Reply-To: kenneth d lewis <kdlewis@JUNO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: kenneth d lewis <kdlewis@JUNO.COM>
Subject: Re: Engine management (manual control of mixture)
Fellow V'gons;
I thought I should elucidate on this theory. First a little O2
sensor background. When the ECU detects the output of the O2 sensor's go
high it "knows" the mixture is too rich and cuts back on the gas
delivery. It waits for the output to go low (lean burn), enrichs the
mixture, and the cycle starts all over. This happens up to several times
per second.
With the opamp between the output and ECU we can "fool" the ECU
by varing the gain above and below a value of one. In other words, with a
gain of 1.1 the ECU's "rich" threshold would be reached sooner causing
the fuel to be cut back quicker. This "should" produce an over all leaner
burn at all RPM ranges.
Drive Safely & Good Luck
Ken Lewis<Kernersville,NC>86 VW crewcab;60 356B Coupe
For Sale: 61 AustinHealey Sprite(not Bugeye);Daily driver $2500
On Sat, 15 Jan 2000 09:16:47 EST kenneth d lewis <kdlewis@JUNO.COM>
writes:
>David;
> I have given this idea some thought. It should be a pretty
>simple circuit, a single, adjustable gain, opamp to massage the
>output of the O2 sensor. Setting the gain below one should enrich the
>mixture and versa-visa. I would want to install some sort of device to
>let me know when I am starting to destroy the engine. Maybe an exhaust
>temperature gauge.
>
>Drive Safely & Good Luck
>Ken Lewis<Kernersville,NC>86 VW crewcab;60 356B Coupe
>For Sale: 61 AustinHealey Sprite(not Bugeye);Daily driver $2500
>
>On Fri, 14 Jan 2000 20:30:13 -0800 David Marshall
><vanagon@VOLKSWAGEN.ORG> writes:
>>I have been toying with the idea of making a black box that would
>>allow the
>>driver to control the mixture of the engine. (If you are with the
>>EPA,
>>please hit delete!)
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________________________________________________________________
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Juno now offers FREE Internet Access!
Try it today - there's no risk! For your FREE software, visit:
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