[Diy_efi] Re: (was: IAC counts) VE tuning issues

Karl Walter krw at efn.org
Sat Jan 1 23:52:15 GMT 2005


This is a multi-part message in MIME format.

--===============49448522758011393==
Content-Type: multipart/alternative;
	boundary="----=_NextPart_000_0029_01C4F019.A0D55280"

This is a multi-part message in MIME format.

------=_NextPart_000_0029_01C4F019.A0D55280
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

I have had trouble with the AIR system bleeding air into the exhaust =
even with the valve "off". Had to plug off the air line whlie tuning.  =
Once I had the idle set, and re-connected everything, it would creep to =
ritch.  Had to replace the valve in the end.   Also had problems with =
the exhaust manifold not sealing at the head on another vehicle and =
giving lean readings on the o2 sensor.  Idle blocks are hard to tune, in =
my opinion, since they have to be lean to pass smog.

--Karl=20
  ----- Original Message -----=20
  From: Mike Frels=20
  To: A list for Do-It-Yourself EFI=20
  Sent: Saturday, January 01, 2005 5:42 AM
  Subject: Re: [Diy_efi] Re: (was: IAC counts) VE tuning issues


  I was reading HELMS this morning(couldn't keep the eyelids open past =
11:00 last night) AIR should only inject into the exhaust manifolds when =
cold and in open loop to help burn converter destroying unburned fuel. =
When it warms and goes closed the AIR should then divert to the =
converter. I interpret this to mean the AIR system should have no =
influence on my 02 readings.

  Just the same I am going to double check for proper operation today. =
Hmmm...could I have switched the two connectors to the diverter valve =
last time I reassembled after checking lifter preload?...I've done worse =
before!...

  I will report on progress as it happens. Yesterday's forecast for =
today was 50% chance of rain.

  Happy New Year,
  Mike

  At 10:04 PM 12/31/2004, you wrote:

    that may be the problem... while tuning, plug the AIR system as it =
injects air to the exhaust like a giant leak...
    =20
    =20
    -------Original Message-------
    =20
    From: Mike Frels
    Date: 12/31/04 21:54:09
    To: A list for Do-It-Yourself EFI
    Subject: Re: [Diy_efi] Re: (was: IAC counts) VE tuning issues
    =20
    Don't you mean 'injectors are much SMALLER than #24 they are =
supposed to be?'
    =20
    Anyway as far as oxygen getting into the exhaust stream the only =
thing I
    have really checked is proper AIR system operation. That is working =
as it
    should. I have not re-checked that exhaust manifold bolts since =
spring when
    I put the engine in. Yes, I am still running cast iron manifolds. I =
will
    take a wrench to the exhaust bolts and nuts tomorrow. Thanks for =
that
    possible pointer.
    =20
    The injectors are brand new Accel 24 pounders. No, I did not have =
them
    flowed before installing as I believed I could trust them from the =
factory.
    Is experience counter to this?
    =20
    Mike
    =20
    At 05:59 PM 12/31/2004, you wrote:
    >I look at it this way:  BLM's greater than 128 means the ECM is =
having to
    >add fuel to keep the mixture right.  This means it's getting more =
air than
    >it should according to the VE tables, which means the table values =
need to
    >be raised by the appropriate factor.  [(BLM/128)*current VE] is a =
very
    >good formula for finding how much to adjust it.
    >
    >If you're getting 160 BLM's and you have 80's in the low-rpm VE =
table,
    >then either your injectors are much bigger than the 24# that you =
think
    >they are, or you have a pretty significant vacuum leak, or you're =
getting
    >a false lean reading from the O2.  First thing to do is check for =
exhaust
    >leaks before/near the O2, as that will REALLY screw with your BLMs. =
 Where
    >did you get the injectors?  Are they new or used, and have they =
been flow
    >tested?



-------------------------------------------------------------------------=
-----


  _______________________________________________
  diy_efi mailing list
  diy_efi at diy-efi.org
  http://lists.diy-efi.org/mailman/listinfo/diy_efi

------=_NextPart_000_0029_01C4F019.A0D55280
Content-Type: text/html;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=3DContent-Type content=3D"text/html; =
charset=3Diso-8859-1">
<META content=3D"MSHTML 6.00.2800.1106" name=3DGENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><FONT face=3DArial size=3D2>I have had trouble with the AIR system =
bleeding air=20
into the exhaust even with the valve "off". Had to plug off the air line =
whlie=20
tuning.&nbsp;&nbsp;Once I had the idle set, and re-connected everything, =
it=20
would creep to ritch.&nbsp; Had&nbsp;to replace the valve in the=20
end.&nbsp;&nbsp;&nbsp;Also had problems with the exhaust manifold not =
sealing at=20
the head on another vehicle and giving lean readings on the o2 =
sensor.&nbsp;=20
Idle blocks are hard to tune, in my opinion, since they have to be lean =
to pass=20
smog.</FONT></DIV>
<DIV>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>--Karl</FONT>&nbsp;</DIV>
<BLOCKQUOTE=20
style=3D"PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; =
BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
  <DIV style=3D"FONT: 10pt arial">----- Original Message ----- </DIV>
  <DIV=20
  style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>=20
  <A title=3Dmfrels at ix.netcom.com =
href=3D"mailto:mfrels at ix.netcom.com">Mike=20
  Frels</A> </DIV>
  <DIV style=3D"FONT: 10pt arial"><B>To:</B> <A =
title=3Ddiy_efi at diy-efi.org=20
  href=3D"mailto:diy_efi at diy-efi.org">A list for Do-It-Yourself EFI</A> =
</DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Saturday, January 01, =
2005 5:42=20
  AM</DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Subject:</B> Re: [Diy_efi] Re: =
(was: IAC=20
  counts) VE tuning issues</DIV>
  <DIV><BR></DIV>I was reading HELMS this morning(couldn't keep the =
eyelids open=20
  past 11:00 last night) AIR should only inject into the exhaust =
manifolds when=20
  cold and in open loop to help burn converter destroying unburned fuel. =
When it=20
  warms and goes closed the AIR should then divert to the converter. I =
interpret=20
  this to mean the AIR system should have no influence on my 02=20
  readings.<BR><BR>Just the same I am going to double check for proper =
operation=20
  today. Hmmm...could I have switched the two connectors to the diverter =
valve=20
  last time I reassembled after checking lifter preload?...I've done =
worse=20
  before!...<BR><BR>I will report on progress as it happens. Yesterday's =

  forecast for today was 50% chance of rain.<BR><BR>Happy New=20
  Year,<BR>Mike<BR><BR>At 10:04 PM 12/31/2004, you wrote:<BR>
  <BLOCKQUOTE class=3Dcite cite=3D"" type=3D"cite">that may be the =
problem... while=20
    tuning, plug the AIR system as it injects air to the exhaust like a =
giant=20
    leak...<BR>&nbsp;<BR>&nbsp;<BR><I>-------Original=20
    Message-------<BR></I>&nbsp;<BR><B><I>From:</I></B> <A=20
    href=3D"mailto:mfrels at ix.netcom.com">Mike =
Frels</A><BR><B><I>Date:</I></B>=20
    12/31/04 21:54:09<BR><B><I>To:</I></B> <A=20
    href=3D"mailto:diy_efi at diy-efi.org">A list for Do-It-Yourself=20
    EFI</A><BR><B><I>Subject:</I></B> Re: [Diy_efi] Re: (was: IAC =
counts) VE=20
    tuning issues<BR>&nbsp;<BR>Don't you mean 'injectors are much =
SMALLER than=20
    #24 they are supposed to be?'<BR>&nbsp;<BR>Anyway as far as oxygen =
getting=20
    into the exhaust stream the only thing I<BR>have really checked is =
proper=20
    AIR system operation. That is working as it<BR>should. I have not =
re-checked=20
    that exhaust manifold bolts since spring when<BR>I put the engine =
in. Yes, I=20
    am still running cast iron manifolds. I will<BR>take a wrench to the =
exhaust=20
    bolts and nuts tomorrow. Thanks for that<BR>possible=20
    pointer.<BR>&nbsp;<BR>The injectors are brand new Accel 24 pounders. =
No, I=20
    did not have them<BR>flowed before installing as I believed I could =
trust=20
    them from the factory.<BR>Is experience counter to=20
    this?<BR>&nbsp;<BR>Mike<BR>&nbsp;<BR>At 05:59 PM 12/31/2004, you=20
    wrote:<BR>&gt;I look at it this way:&nbsp; BLM's greater than 128 =
means the=20
    ECM is having to<BR>&gt;add fuel to keep the mixture right.&nbsp; =
This means=20
    it's getting more air than<BR>&gt;it should according to the VE =
tables,=20
    which means the table values need to<BR>&gt;be raised by the =
appropriate=20
    factor.&nbsp; [(BLM/128)*current VE] is a very<BR>&gt;good formula =
for=20
    finding how much to adjust it.<BR>&gt;<BR>&gt;If you're getting 160 =
BLM's=20
    and you have 80's in the low-rpm VE table,<BR>&gt;then either your =
injectors=20
    are much bigger than the 24# that you think<BR>&gt;they are, or you =
have a=20
    pretty significant vacuum leak, or you're getting<BR>&gt;a false =
lean=20
    reading from the O2.&nbsp; First thing to do is check for=20
    exhaust<BR>&gt;leaks before/near the O2, as that will REALLY screw =
with your=20
    BLMs.&nbsp; Where<BR>&gt;did you get the injectors?&nbsp; Are they =
new or=20
    used, and have they been flow<BR>&gt;tested?<BR></BLOCKQUOTE>
  <P>
  <HR>

  <P></P>_______________________________________________<BR>diy_efi =
mailing=20
  =
list<BR>diy_efi at diy-efi.org<BR>http://lists.diy-efi.org/mailman/listinfo/=
diy_efi<BR></BLOCKQUOTE></BODY></HTML>

------=_NextPart_000_0029_01C4F019.A0D55280--


--===============49448522758011393==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
diy_efi mailing list
diy_efi at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/diy_efi

--===============49448522758011393==--




More information about the Diy_efi mailing list