O2 sensor idea

Bruce Plecan nacelp at bright.net
Tue Apr 20 04:18:39 GMT 1999


----- Original Message -----
From: Steve Gorkowski <kb4mxo at mwt.net>
To: <diy_efi at efi332.eng.ohio-state.edu>
Sent: Monday, April 19, 1999 9:23 PM
Subject: Re: O2 sensor idea


> Isn't this the basics Bruce (NO flame)
> On unleaded you can't read color (other than red , way over rich ,way lean
,oil
> , and other engine failures )

Red/pink, mangenese additive-change brands.
Can't read color or too white check for alky content of fuel (test
tube+eyedropper)
If plug burns reflecting either of the above, change brands

Oil obvious

and you can't use wb O2 alone Bruce ,

I never said you should/could use a WB O2 alone.

a
> accelerometer will tell you when your near the proper AFR (I am now using
> standard O2 sensor) . Read that value (led) then do a read of a plug and
see if
> your not way rich or lean or any other problem.

ONCE YOU DETERMINE your optimim combination then you can use the oem O2 as a
guage, meaning you have a sudden failure if the lights don't apprear.
Just don't tune to .8345729448837393893 volts and think your safe cause you
should be at 12.3989948923823395032390238984:1 Air Fuel Ratio.
   I've always stressed starting rich and leaning down, for someone to say
he's too lean means he's tried to short circuit doing the tuning.
  By example if there are 500 rpm steps for WOT AFR, and you shift at 6,000,
and your recovery rpm is 3,000 rpm, that would be 6 steps, well to get those
6 steps right is gonna take 2 dozen passes to dial in correctly.  Your not
going to know what the engine wants till ya try it.  Once you have things
dialed in then you know your target AFR.
Bruce

> Then change temp. range of plugs ( hardly ever do this ) . No expert but
if you
> change type of plugs start over. Every time you rebuild the engine change
cam
> ect. start over. Change RPM band start over. Index plugs start over.

If your so far off the tune that your experimenting with heat range
surprise, yes your startingover.   Changing cams, unless making a huge
change you'll bbe 1/2 close.  If your serious about tuning you're indexing
the plugs anyway.
>
> Steve
> Steve
> Bruce Plecan wrote:
> > By sharpening your skills, there are other signs than color to tell ya
whats
> > going on.   Running a Horiba on each cylinder won't tell ya diddly about
> > plug temp either.
> > Sounds like your trying to tune to a AFR rather then what performs best.
> >   I absolutely guarantee ya I can tune a car to 12.5:1 (or any AFR you
> > pick), and can hole a piston....
> >   Tell me how you find transistionial ping/detonation with a WB O2.
> > So, without p--- - c---, how are you going to do this.
> >   I can appreciate liking an easy answer but it just ain't gonna work
that
> > way.
> > Bruce
> > > And bruce, quit saying plug cuts, plug cuts do nothing for telling you
> > > if you are rich at 4000rpm and lean at 5000rpm just what the average
> > > is.
> > > Roger





More information about the Diy_efi mailing list