ECM F/A1000, Instruction Manual, Page: 13 / 26

9
Pressure Compensation Equation for F/A
F/A(corrected) = (F/A(measured) + aP) / (1 + bP) [Equation 3a]
where: F/A(corrected) = the F/A corrected for exhaust pressure.
F/A(measured) = the F/A output by the F/A.
a = 4.30x10
-5
for F/A > 0.0686 (rich).
a = 5.70x10
-5
for F/A ≤ 0.0686 (lean).
b = 6.27x10
-4
for F/A > 0.0686 (rich).
b = 8.30x10
-4
for F/A ≤ 0.0686 (lean).
P = the exhaust pressure in mmHg above the pressure at which
the sensor was calibrated (using the CAL POT on the F/A
Monitor while the sensor is held in air). Equation 3 is valid
for -152 mmHg < P < 532 mmHg.
Pressure Compensation Equation for Lambda
Lambda(corrected) = (Lambda(measured) + B x P) / (1 + B x P) [Equation 3b]
where: Lambda(corrected) = the Lambda corrected for exhaust pressure.
Lambda(measured) = the Lambda output by the F/A.
B = 0.000627 for Lambda < 1.0 (rich).
B = 0.000830 for Lambda ≥ 1.0 (lean).
P = the exhaust pressure in mmHg above the pressure at which
the sensor was calibrated (using the CAL POT on the
AFM while the sensor is held in air). Equation 3b is valid
for -152 mmHg < P < 532 mmHg.
Pressure Compensation Equation for %O
2
% O
2
(corrected) = %O
2
(measured) / [1.0 + B x P] [Equation 3c]
where: %O
2
(corrected) = the %O
2
corrected for exhaust pressure.
%O
2
(measured) = the %O
2
output by the F/A.
B = 0.000830
P = the exhaust pressure in mmHg above the pressure at which
the sensor was calibrated (using the CAL POT on the
AFM while the sensor is held in air). Equation 3c is valid
for -152 mmHg < P < 532 mmHg.