Remove me from this list please

Patrick Anglum panglum at nortelnetworks.com
Tue Dec 7 15:35:29 GMT 1999


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Patrick Anglum
Passport 4400 Development
4100 Guardian Street  M/S NE
Simi Valley, CA 93063-3397
panglum at nortelnetworks.com
> % (805) 577-2288  
> %  ESN 495-2288
> 
> 
> 
> -----Original Message-----
> From:	DIY_EFI-Digest-Owner at efi332.eng.ohio-state.edu
> [SMTP:DIY_EFI-Digest-Owner at efi332.eng.ohio-state.edu]
> Sent:	Sunday, December 05, 1999 12:00 PM
> To:	DIY_EFI-Digest at efi332.eng.ohio-state.edu
> Subject:	DIY_EFI Digest V4 #677
> 
> 
> DIY_EFI Digest        Sunday, December 5 1999        Volume 04 : Number
> 677
> 
> 
> 
> In this issue:
> 
> 	Re: Ref. Signal off of AMC I6
> 	mem-cal
> 	Add-on systems which affect output pulse width?
> 
> See the end of the digest for information on subscribing to the 
> DIY_EFI or DIY_EFI-Digest mailing lists.
> 
> ----------------------------------------------------------------------
> 
> Date: Sun, 05 Dec 1999 09:32:45 -0500
> From: Shannen Durphey <shannen at grolen.com>
> Subject: Re: Ref. Signal off of AMC I6
> 
> > 
> > Date: Sun, 5 Dec 1999 00:56:23 -0500 (EST)
> > From: Mike Comai <comai at expert.cc.purdue.edu>
> > Subject: Ref. Signal off of AMC I6
> > 
> > I am currently trying to get my first major retrofit up and running.  I
> > have everything installed and when I try to start it the injector's
> don't
> > fire.  I was told that I need a filter on the negative side of the coil
> > and to feed the filtered signal into the Reference line on the ECM
> (which
> > I am using a '747).  I was given a design for a filter which looks like
> > this:
> >                5K               10K
> > Coil    -----/\/\/\/---------/\/\/\/\------------ ECM
> >                         |               |
> >                       -----           -----
> >                       ----- 15uf      -----100pf
> >                         |               |
> >                        gnd             gnd
> > 
> 
> From a mechanic's point of view, (and because there's little other
> info to work with) why haven't you adapted a GM ignition module to the
> AMC dizzy?  The voltage on the negative side of the coil "bounces"
> after the plug fires, and your ecm may be getting what it thinks are
> several reference pulses when it should get one.  'Course this is a
> rough guess.... you might try to get a scan tool and watch rpm
> readings during cranking to verify this.  Another possibility is that
> everything is ok but your calibration is wrong, or your injectors are
> wrong, or the coil isn't firing because the reference line is
> grounding out the signal from the dizzy.
> 
> Also, if you're running the reference line from the distributor, do
> you have the est line connected?  Where?  One of the great benefits of
> using an ecm is computer controlled spark.  Without it, you're not
> realizing the full potential of your project.
> Shannen
> 
> > When the filter is in place, the injector don't fire.  When I remove the
> > filter and connect the coil directly to the ecm it appears to flood out
> > the engine :( If someone could explain what voltages levels and shapes
> are
> > present on the neg. side of the coil and what it needs to get
> conditioned
> > to for the ECM that would be great too.  Appreciate any help yall could
> > give.
> > 
> > Mike Comai
> > '79 CJ5
> > 
> > ------------------------------
> > 
> > End of DIY_EFI Digest V4 #676
> > *****************************
> > 
> > To subscribe to DIY_EFI-Digest, send the command:
> > 
> >     subscribe diy_efi-digest
> > 
> > in the body of a message to "Majordomo at efi332.eng.ohio-state.edu".
> > 
> > A non-digest (direct mail) version of this list is also available; to
> > subscribe to that instead, replace "diy_efi-digest" in the command
> >  above with "diy_efi".
> 
> ------------------------------
> 
> Date: Sun, 5 Dec 1999 10:33:21 -0700
> From: cwagner at info2000.net
> Subject: mem-cal
> 
> Does anyone have any sugestions on what memcal I could get for 
> running a 4 cyl engine using a 747 computer?  Or could I make one 
> out of some spare resistors.
> 
> ------------------------------
> 
> Date: Sun, 05 Dec 1999 11:43:02 -0800
> From: "Andrew Brownsword" <asword at telus.net>
> Subject: Add-on systems which affect output pulse width?
> 
> Hello again,
> 
>   After posting my project description yesterday I spent some time surfing
> the web for add-on computers.  All the systems I have seen so far seem to
> work their magic by modifying the airflow meter's voltage input to the
> ECU.
> The ECU is then relied on to "do the right thing".
> 
>   It seems to me that this could be problematic if the ECU was designed to
> expect a particular voltage range and the stock airflow meter generated
> that
> full range ... in other words there is no buffer for going beyond the
> expected range of values.  This seems fairly reasonable for an N/A engine
> since it is extremely unlikely that the car will have to deal with >1
> atmosphere.
> 
>   It seems pretty obvious that most add-on computers are designed to
> modify
> input because it is easy.  The computer reads one voltage, maps it through
> a
> table, and outputs another voltage.
> 
>   The alternative is to modify the ECU's output, which is a time dependant
> pulse width.  It simply isn't possible to have full remapping control over
> the output because by the time you know what the pulse width is, the time
> at
> which you have to send it to the injectors has passed.  It occurred to me
> this morning, however, that an add-on computer could fairly easily extend
> (not shorten) the pulse width based on input from a pressure sensor.  It
> would read its own MAP sensor to determine the amount of "extra" fuel
> needed
> beyond the amount the stock ECU has calculated (being tuned for where the
> ECU's airflow meter saturates), detect the trailing edge of the ECU's
> pulse,
> and keep the pulse going for that extra time.
> 
>   So am I off my rocker here?  Is this possible?  Has anybody built a
> product which does this?  Is this even an issue, or does a stock ECU
> program
> ALWAYS allow enough buffer that input modification is a better approach?
> 
>   I hope I'm not reiterating common questions or wandering too far from
> the
> list charter -- I haven't seen a FAQ for this list yet, so please bear
> with
> me.  And if there is a FAQ, you somebody point me at it?
> 
> Cheers,
>    Andrew
> 
> ------------------------------
> 
> End of DIY_EFI Digest V4 #677
> *****************************
> 
> To subscribe to DIY_EFI-Digest, send the command:
> 
>     subscribe diy_efi-digest
> 
> in the body of a message to "Majordomo at efi332.eng.ohio-state.edu".  
> 
> A non-digest (direct mail) version of this list is also available; to
> subscribe to that instead, replace "diy_efi-digest" in the command
>  above with "diy_efi".
> 

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<P><FONT COLOR=3D"#0000FF" SIZE=3D6 FACE=3D"Brush Script MT">Patrick =
Anglum</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">Passport 4400 Development</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">4100 Guardian Street&nbsp; M/S =
NE</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">Simi Valley, CA 93063-3397</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">panglum at nortelnetworks.com</FONT>
<BR><FONT COLOR=3D"#808080" FACE=3D"Monotype Sorts">%</FONT><FONT =
SIZE=3D2 FACE=3D"Arial"> (805) 577-2288&nbsp; </FONT>
<BR><FONT COLOR=3D"#808080" FACE=3D"Monotype Sorts">%</FONT><FONT =
SIZE=3D2 FACE=3D"Arial">&nbsp; ESN 495-2288</FONT>
</P>
<BR>
<BR>
<UL>
<P><FONT SIZE=3D1 FACE=3D"Arial">-----Original Message-----</FONT>
<BR><B><FONT SIZE=3D1 FACE=3D"Arial">From:&nbsp;&nbsp;</FONT></B> <FONT =
SIZE=3D1 FACE=3D"Arial">DIY_EFI-Digest-Owner at efi332.eng.ohio-state.edu =
[SMTP:DIY_EFI-Digest-Owner at efi332.eng.ohio-state.edu]</FONT>
<BR><B><FONT SIZE=3D1 FACE=3D"Arial">Sent:&nbsp;&nbsp;</FONT></B> <FONT =
SIZE=3D1 FACE=3D"Arial">Sunday, December 05, 1999 12:00 PM</FONT>
<BR><B><FONT SIZE=3D1 =
FACE=3D"Arial">To:&nbsp;&nbsp;&nbsp;&nbsp;</FONT></B> <FONT SIZE=3D1 =
FACE=3D"Arial">DIY_EFI-Digest at efi332.eng.ohio-state.edu</FONT>
<BR><B><FONT SIZE=3D1 =
FACE=3D"Arial">Subject:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT>=
</B> <FONT SIZE=3D1 FACE=3D"Arial">DIY_EFI Digest V4 #677</FONT>
</P>
<BR>

<P><FONT SIZE=3D2 FACE=3D"Arial">DIY_EFI =
Digest&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Sunday, December 5 =
1999&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Volume 04 : Number =
677</FONT>
</P>
<BR>
<BR>

<P><FONT SIZE=3D2 FACE=3D"Arial">In this issue:</FONT>
</P>

<P>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">Re: Ref. Signal off of AMC I6</FONT>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">mem-cal</FONT>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">Add-on systems which affect output pulse width?</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">See the end of the digest for =
information on subscribing to the </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">DIY_EFI or DIY_EFI-Digest mailing =
lists.</FONT>
</P>

<P><FONT SIZE=3D2 =
FACE=3D"Arial">---------------------------------------------------------=
-------------</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Date: Sun, 05 Dec 1999 09:32:45 =
-0500</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">From: Shannen Durphey =
&lt;shannen at grolen.com&gt;</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">Subject: Re: Ref. Signal off of AMC =
I6</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; Date: Sun, 5 Dec 1999 00:56:23 =
-0500 (EST)</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; From: Mike Comai =
&lt;comai at expert.cc.purdue.edu&gt;</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; Subject: Ref. Signal off of AMC =
I6</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; I am currently trying to get my =
first major retrofit up and running.&nbsp; I</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; have everything installed and =
when I try to start it the injector's don't</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; fire.&nbsp; I was told that I =
need a filter on the negative side of the coil</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; and to feed the filtered signal =
into the Reference line on the ECM (which</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; I am using a '747).&nbsp; I was =
given a design for a filter which looks like</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; this:</FONT>
<BR><FONT SIZE=3D2 =
FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
5K&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbs=
p;&nbsp;&nbsp; 10K</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; Coil&nbsp;&nbsp;&nbsp; =
-----/\/\/\/---------/\/\/\/\------------ ECM</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbs=
p;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbs=
p;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp; |</FONT>
<BR><FONT SIZE=3D2 =
FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp; =
-----&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
-----</FONT>
<BR><FONT SIZE=3D2 =
FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp; ----- 15uf&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; -----100pf</FONT>
<BR><FONT SIZE=3D2 =
FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp; =
|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp; |</FONT>
<BR><FONT SIZE=3D2 =
FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp; =
gnd&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nb=
sp; gnd</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">From a mechanic's point of view, (and =
because there's little other</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">info to work with) why haven't you =
adapted a GM ignition module to the</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">AMC dizzy?&nbsp; The voltage on the =
negative side of the coil &quot;bounces&quot;</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">after the plug fires, and your ecm =
may be getting what it thinks are</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">several reference pulses when it =
should get one.&nbsp; 'Course this is a</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">rough guess.... you might try to get =
a scan tool and watch rpm</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">readings during cranking to verify =
this.&nbsp; Another possibility is that</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">everything is ok but your calibration =
is wrong, or your injectors are</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">wrong, or the coil isn't firing =
because the reference line is</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">grounding out the signal from the =
dizzy.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Also, if you're running the reference =
line from the distributor, do</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">you have the est line =
connected?&nbsp; Where?&nbsp; One of the great benefits of</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">using an ecm is computer controlled =
spark.&nbsp; Without it, you're not</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">realizing the full potential of your =
project.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">Shannen</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&gt; When the filter is in place, the =
injector don't fire.&nbsp; When I remove the</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; filter and connect the coil =
directly to the ecm it appears to flood out</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; the engine :( If someone could =
explain what voltages levels and shapes are</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; present on the neg. side of the =
coil and what it needs to get conditioned</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; to for the ECM that would be =
great too.&nbsp; Appreciate any help yall could</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; give.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; Mike Comai</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; '79 CJ5</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; =
------------------------------</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; End of DIY_EFI Digest V4 =
#676</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; =
*****************************</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; To subscribe to DIY_EFI-Digest, s=
end the command:</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt; </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&gt;&nbsp;&nbsp;&nbsp;&nbsp; =
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</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">------------------------------</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Date: Sun, 5 Dec 1999 10:33:21 =
-0700</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">From: cwagner at info2000.net</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">Subject: mem-cal</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Does anyone have any sugestions on =
what memcal I could get for </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">running a 4 cyl engine using a 747 =
computer?&nbsp; Or could I make one </FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">out of some spare resistors.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">------------------------------</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Date: Sun, 05 Dec 1999 11:43:02 =
-0800</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">From: &quot;Andrew Brownsword&quot; =
&lt;asword at telus.net&gt;</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">Subject: Add-on systems which affect =
output pulse width?</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Hello again,</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp; After posting my project =
description yesterday I spent some time surfing</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">the web for add-on computers.&nbsp; =
All the systems I have seen so far seem to</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">work their magic by modifying the =
airflow meter's voltage input to the ECU.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">The ECU is then relied on to &quot;do =
the right thing&quot;.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp; It seems to me that this could =
be problematic if the ECU was designed to</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">expect a particular voltage range and =
the stock airflow meter generated that</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">full range ... in other words there =
is no buffer for going beyond the</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">expected range of values.&nbsp; This =
seems fairly reasonable for an N/A engine</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">since it is extremely unlikely that =
the car will have to deal with &gt;1</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">atmosphere.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp; It seems pretty obvious that =
most add-on computers are designed to modify</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">input because it is easy.&nbsp; The =
computer reads one voltage, maps it through a</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">table, and outputs another =
voltage.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp; The alternative is to modify =
the ECU's output, which is a time dependant</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">pulse width.&nbsp; It simply isn't =
possible to have full remapping control over</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">the output because by the time you =
know what the pulse width is, the time at</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">which you have to send it to the =
injectors has passed.&nbsp; It occurred to me</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">this morning, however, that an add-on =
computer could fairly easily extend</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">(not shorten) the pulse width based =
on input from a pressure sensor.&nbsp; It</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">would read its own MAP sensor to =
determine the amount of &quot;extra&quot; fuel needed</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">beyond the amount the stock ECU has =
calculated (being tuned for where the</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">ECU's airflow meter saturates), =
detect the trailing edge of the ECU's pulse,</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">and keep the pulse going for that =
extra time.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp; So am I off my rocker =
here?&nbsp; Is this possible?&nbsp; Has anybody built a</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">product which does this?&nbsp; Is =
this even an issue, or does a stock ECU program</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">ALWAYS allow enough buffer that input =
modification is a better approach?</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp; I hope I'm not reiterating =
common questions or wandering too far from the</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">list charter -- I haven't seen a FAQ =
for this list yet, so please bear with</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">me.&nbsp; And if there is a FAQ, you =
somebody point me at it?</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Cheers,</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;&nbsp; Andrew</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">------------------------------</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">End of DIY_EFI Digest V4 #677</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">*****************************</FONT>
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