Jeep 1987 Wrangler Workshop Manual page 517

4 ^
ENGINES
4 ^
FUEL FEEDBACK SYSTEMS
CONTINUED
FROM PREVIOUS
PAGE
OBSERVE STEPPER MOTOR METERING PINS PINS
SHOULD BE IN LEAN POSITION (TOWARD REAR OF
ENGINE)
CONTINUED
F R O M P R E V I O U S
P A G E
DISCONNECT OXYGEN
SENSOR CONNECTOR AND
TEST VOLTAGE AT
OXYGEN SENSOR
STEPPER MOTOR PINS ARE
AT MIDWAY TO FULL RICH
POSITION. REPLACE MCU
AND RETEST STEPPER
MOTOR PIN POSITION.
REPAIR WIRE HARNESS INSPECT FOR LARGE AIR
BETWEEN 0
2
SENSOR LEAK INTO MANIFOLD
CONNECTOR AND MCU VACUUM IF OK. REPLACE
CONNECTOR OXYGEN SENSOR
START ENGINE AND OPERATE FOR 40 SECONDS. INCREASE ENGINE SPEED TO MORE
THAN 1000 RPM AND LOAD ENGINE ( E.G., A C ON). OBSERVE STEPPER MOTOR PIN
MOVEMENT. PINS SHOULD MOVE FORE AND AFT OF A FIXED POINT.
B-283
81135B