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<DIV><FONT color=#000000 size=2>Engine is pretty much stock with the exception
of a 214/224 cam and roller rockers. It had some mild flow improvement in the
intake department and exhaust is cat free.</FONT><FONT color=#000000 size=2> The
combo worked flawlessly when it was in my Chevelle with a 600 CFM
carb.</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT><FONT size=2>A little more info on it.
When I time it to 6 deg, it will like I said idle fine. As soon as I plug the
connector back in however, the retard kicks way in. I figure with the connector
connected, timing should be somewhere around the 6 degrees that I set + the
amount the chip is set, so I figured it is around 18 degrees if everything was
working correctly. When I turn the distributor so the timing mark goes from
18-24 degrees after top dead center to about 18 degrees before top dead center,
she will rev up and drive around normally for the most part. The problem is,
when I turn the car off, disconnect the timing connector, I can barely start it
again and the timing is about 25 degrees advanced because of how much I had to
turn it previously.</FONT></DIV>
<DIV><FONT size=2>Here is the bin. It is the stock one (HLH 3200) with the
pulsewidth trimmed down a bit and not much else done to it besides fans, etc. I
tried to disable the Spark Control Diagnostic thinking that this was erroneously
retarding 20 degrees for no reason, but it made no difference.</FONT></DIV>
<DIV><FONT color=#000000 size=2>I don't have the EGR solenoid hooked up, nor do
I have an EGR valve, air diverter solenoid, or the other emissions stuff. Could
the fact that these are not hooked up (even though no codes are thrown) make the
computer go into a full retard because if they are open, then they are not
completing the 12 volt circuit and the computer thinks there is a
problem?</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT><FONT size=2>One last question. My helms
manual for the 85 Vette states on pin D10 the exact type: "POWER GROUND
?" It had the '?' there. I do not have a ground there, but who
knows.</FONT></DIV>
<DIV><FONT size=2>Thanks again, -Matt-</FONT></DIV>
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<DIV><FONT face=Arial size=2><B>-----Original Message-----</B><BR><B>From:
</B>Programmer <<A
href="mailto:nwester@eidnet.org">nwester@eidnet.org</A>><BR><B>To: </B><A
href="mailto:gmecm@diy-efi.org">gmecm@diy-efi.org</A> <<A
href="mailto:gmecm@diy-efi.org">gmecm@diy-efi.org</A>><BR><B>Date:
</B>Friday, May 11, 2001 7:50 PM<BR><B>Subject: </B>Re: 870 Spark
Control<BR><BR></DIV></FONT>
<DIV><FONT face="Book Antiqua" size=2>Can you give me a little history
here--is this a modded unit, or totally factory. Can you upload your bin to
me ?</FONT></DIV>
<DIV><FONT face="Book Antiqua" size=2></FONT> </DIV>
<DIV><FONT face="Book Antiqua" size=2>Lyndon.</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A href="mailto:msandine@purdue.edu" title=msandine@purdue.edu>Matt
Sandine</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
href="mailto:gmecm@diy-efi.org"
title=gmecm@diy-efi.org>gmecm@diy-efi.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, May 11, 2001 1:46
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: 870 Spark
Control</DIV>
<DIV><BR></DIV>
<DIV><FONT size=2>I am not kidding. It bucks and sputters all over the
place, but that is what is really happening. You can tell the fuel is
totally being ignited at the wrong time. I thought my timing light could
be way outta wack. I used another with the same results. She purrs like
a kitten when the timing connector is disconnected and it is at 6 deg,
besides the fact that you can't rev it because the computer isn't adding
the spark. Just in case the balancer was slipping, I marked the pulley.
It is honestly retarding the spark at least 20 degrees from the
6.</FONT></DIV>
<DIV><FONT size=2>Does this make sense? The only way I have been able to
figure out spark advance on the 85 (since it doesn't show it in scan
tools) besides using a timing light is to use a scope on the pickup coil
input and EST output at the computer harness. By tracking both of these
waves at the same time, I was able to see the EST get tighter and
tighter compared to the pickup coil pulse remaining constant. Only
problem is, I need to try to figure out if the EST pulse is actually
being retarded from the computer or if it is being retarded at the ESC
module. Thanks for the interest Lyndon, -Matt-</FONT></DIV>
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<DIV><FONT face=Arial size=2><BR> </DIV></FONT>
<DIV><FONT face="Book Antiqua" size=2>Matt,</FONT></DIV>
<DIV><FONT face="Book Antiqua" size=2></FONT> </DIV>
<DIV><FONT face="Book Antiqua" size=2>If this thing was going into
24 degrees retard from 6 BTDC, it'd stall. Are you 100% sure it's
going 24 ATDC ?</FONT></DIV>
<DIV><FONT face="Book Antiqua" size=2></FONT> </DIV>
<DIV><FONT face="Book Antiqua" size=2>Lyndon.</FONT></DIV>
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