CO Emissions

Wed Apr 9 19:57:24 GMT 1997

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Steve, thanks for the reply.  I stated the problem wrong yesterday.  Here is the
actual situation:  HC 455/450 loaded-fail, 459/450 idle-fail
                   CO 1.05/3.75 loaded-pass, 0.74/5.00 idle-pass
I changed my O2 trigger level from .57 to .60 for the idle and loaded areas 
which resulted in todays readings:
                   HC 393/450 loaded-pass, 486/450 idle-fail
                   CO 1.51/3.75 loaded-pass, 0.85/5.00 idle-pass
This change corrected the loaded readings as expected and the idle CO as well, 
but did not effect the idle HC as expected.  What are causes for ignition 
misfire?  After checking the obvious, wire, plugs, vacuum leaks, what adjustment
do you think I can make to the FI and ignition that might improve the idle HC.  
I can change the idle O2 trigger voltage separately and I can adjust the 
ignition timing over the whole range.  Since this is a closed loop system any 
changes to the fuel map are nulified by the O2 sensor loop.  I'm currently 
running 10 degrees of advance at idle.  Thanks, me.
>
> Text item:
>
> Its been a while since I've been on the list.  I've changed jobs...
> Anyway my CO emissions are slightly over spec, 555/550.  Does this
> mean I'm running rich or lean?  I've had responses both ways from
> different sources and now I'm asking the experts how much I should
> increase or decrease my O2 sensor voltage trigger point on a closed
> loop system to correct this problem?  I can save $10.00 if I get it
> right the first time.  Thanks, me.

High CO means rich.  Not enough oxygen to reduce the CO to CO2.  When
passing emissions tests, keep this in mind:

High CO and high HC means you are rich.  High HC and normal CO
means ignition misfire.

--steve

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In-Reply-To: <Tue, 08 Apr 97 17:50:52 PDT_11 at ccm.fm.intel.com>
Priority: normal
Reply-To: steve at imes.com
Subject: Re: CO Emissions
Date: Wed, 9 Apr 1997 08:22:48 +0000
To: Mark Eidson <Mark_Eidson at ccm.ch.intel.com>
From: "steve ravet" <steve at sun4c409.imes.com>
Comments: Authenticated sender is <steve at sun4c409.imes.com>
Message-Id: <9704091453.AA26780 at gaia.imes.com>
1997 14:56:06 GMT
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