Diagnostic Aids

WARNING: This page is about a different car, the 1995 Ford Explorer and 1995 Ford Aerostar. However, it is still accessible from the selected car via links, so may be relevant.

Perform this test when directed by QUICK TEST. PCM uses adaptive fuel logic to compensate for normal variances in fuel system components. If fuel system appears to be too rich or too lean, adaptive fuel will make appropriate shift in fuel delivery calculations to compensate.

If possible, measure several known-good MAP/BARO sensors. Average voltage reading will be typical for location and day of testing.

MAP SENSOR VOLTAGE OUTPUT

Elevation (Feet)	Volts
0	1.55-1.63
1000	1.52-1.60
2000	1.49-1.57
3000	1.46-1.54
4000	1.43-1.51
5000	1.40-1.48
6000	1.37-1.45
7000	1.35-1.43

CIRCUIT TEST HA ACRONYMS

Acronym	Definition
HO2S	Heated Oxygen Sensor
KAM	Keep-Alive Memory
SFI	Sequential Multiport Fuel Injection

1) Continuous Memory Codes 181, 183, 189 & 192 These codes identify a lean fuel condition resulting in adaptive fuel strategy enriching fuel system to compensate.

Code 183

Indicates right or rear HO2S detected a problem and adaptive fuel rich limit has been reached at idle.

Code 192

Indicates left or front HO2S detected a problem and adaptive fuel rich limit has been reached at idle.

Code 181

Indicates right or rear HO2S detected a problem and adaptive fuel rich limit has been reached.

Code 189

Indicates left or front HO2S detected a problem and adaptive fuel rich limit has been reached.