Re: K-Jectronic adjustment

[Orin Eman <orin@wolfenet.com>]

> > I jumpered the fuel pump with the engine off to go through the regular
> > diagnostics and all the default settings seemed fine.  Cold Enrichment -
> > 80%; Full Throttle enrichment - 65%; O2 sensor disconnected - 50%.  When I
> > started the car and let it warm up the Duty Cycle would vary from about 25%
> > to 40%.  Now, on my duty cycle meter 100% corresponds to full lean and 0% is
> > full rich so I assumed the meter was reading backwards as the enrichment
> > settings from Cold start and full throttle are 80% and 65% (which agree with
> > the Bentley values) , and during normal running duty cycle measures 25-40%.
> > So if the car is truly running lean the readings make sense.

> with a working OXS in the circuit the only way the car can run lean is
> if the freq valve can no longer make the engine any richer.

Actually, misfire gives these symptoms:

> > Also the Lambda system seemed to act erratically in that on occasions it
> > would just slowly move over to 100% duty cycle and stay there. The frequency
> > valve would obviously stop cycling at this point. 

When a cyl misfires, the O2 sensor detects lots of O2 in the exhaust
and thinks the engine is running lean.  Hence the gradual stepping
up to 100% duty cycle.  It doesn't usually help the misfiring...

Symptoms are O2 settings indicating lean running, but plugs black
and sooty.  Believe the plugs.  Check plugs, wires, cap and rotor
if your duty cycle is going to 100%.

Orin.