The O2 "method" (Re: MAF/AFM vs. Chip)

[Jim Conforti <lndshrk@xxxxxxxxxxxx>]

Neil writes:

> This is where Jim Conforti's claim that the O2 
> sensor method is not accurate could be tested

My *CLAIM*?!?

Neil, buddy, pal.. it's not my claim.. it's

1) Science

2) Common Sense

3) The MANUFACTURER of said 02 Sensor..

It never fails to amaze me how people blindly disregard
the application of hardware and then wonder why experts
in the field have strokes ;)

Simple facts..

1) The normal Zr02 Qxygen Sensor works via electrochemical
   methods that ONLY will reliably sense Lambda ~= 1.0 both
   due to the theory and the manufacturing tolerances of
   the sensor..  don't believe me.. pick up a BOOK and READ

2) There are *special* Zr02 sensors that are made in a 
   controlled method.. called the Bosch LSM-11.. it can be used
   to read outside Lambda ~= 1.0 ***BUT*** to do so requires
   a complex circuit to measure sensor internal resistance, convert
   it to sensor internal temp and then do a 3d lookup of LAMBDA
   versus the Internal Temp and Output Voltage.. 

   Systems of this type retail for a MINIMUM of $1500.. 

3) There is a 3rd type of sensor.. a pumping cell sensor (NTK/Horiba)
   that also requires a whacko and sensitive circuit to run it..
   you can tell this sensor as it has either FIVE or SIX wires
   versus FOUR.

All in all, trying to tune with a stock O2 sensor can *sometimes*
(if you are lucky) get you CLOSE.. for THAT CAR.. othertimes it
will NOT and you will be hurting the car..

The sensors vary too much from one to the next.. and the attained
temps vary too much from Car A to Car B to bet much on the results

Q.E.D.

Jim Conforti

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