SMU-SEC. 6E ENGINE CONTROLS REVISED

SUBJECT: SERVICE MANUAL UPDATE - SECTION 6E - ENGINE CONTROLS REVISED MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR DESCRIPTION

MODELS: 1996-98 BUICK LESABRE, PARK AVENUE, PARK AVENUE ULTRA, RIVIERA 1996-98 OLDSMOBILE EIGHTY-EIGHT, EIGHTY-EIGHT LS, LSS 1996-98 PONTIAC BONNEVILLE 1996 OLDSMOBILE NINETY-EIGHT 1997 OLDSMOBILE REGENCY 1997 BUICK REGAL, REGAL GRAN SPORT 1997 PONTIAC GRAND PRIX WITH 3.8L ENGINE (VINS 1, K - RPOS L36, L67)

THIS BULLETIN IS BEING ISSUED TO INFORM TECHNICIANS OF A REVISION TO THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR CIRCUIT DESCRIPTIONS FOR DTCS P0107, P0108, P1106, P1107 AND THE MAP SENSOR DESCRIPTION IN THE "INFORMATION SENSORS/SWITCHES DESCRIPTION" LOCATED IN THE "DESCRIPTION AND OPERATION" SECTION.

REPLACE THE CURRENT DESCRIPTIONS IN THE ABOVE LISTED DTCS AND "DESCRIPTION AND OPERATION" SECTIONS WITH THE FOLLOWING REVISIONS:

* DTC P0107 VIN K - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS WITH THE KEY ON, ENGINE NOT RUNNING OR AT WIDE OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS EXCESSIVELY LOW, DTC P0107 WILL BE SET.

VIN 1 - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. WITH THE KEY ON, ENGINE NOT RUNNING, THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES BETWEEN 1.5 TO 2.5 VOLTS. WITH THE ENGINE RUNNING, THE MAP SENSOR VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS EXCESSIVELY LOW, DTC P0107 WILL BE SET.

* DTC P0108 VIN K - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS WITH THE KEY ON, ENGINE NOT RUNNING OR AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS EXCESSIVELY HIGH, DTC P0108 WILL BE SET.

VIN 1 - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. WITH THE KEY ON, ENGINE NOT RUNNING, THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES BETWEEN 1.5 TO 2.5 VOLTS. WITH THE ENGINE RUNNING, THE MAP SENSOR VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS EXCESSIVELY LOW, DTC P0107 WILL BE SET.

* DTC P1106 VIN K - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS WITH THE KEY ON, ENGINE NOT RUNNING OR AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS INTERMITTENTLY HIGH, DTC P1106 WILL BE SET.

VIN 1 - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. WITH THE KEY ON, ENGINE NOT RUNNING, THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES BETWEEN 1.5 TO 2.5 VOLTS. WITH THE ENGINE RUNNING, THE MAP SENSOR VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS INTERMITTENTLY HIGH, DTC P1106 WILL BE SET.

* DTC P1107 VIN K - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS WITH THE KEY ON, ENGINE NOT RUNNING OR AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS INTERMITTENTLY LOW, DTC P1107 WILL BE SET.

VIN 1 - THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. WITH THE KEY ON, ENGINE NOT RUNNING, THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES BETWEEN 1.5 TO 2.5 VOLTS. WITH THE ENGINE RUNNING, THE MAP SENSOR VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A MAP SIGNAL VOLTAGE THAT IS INTERMITTENTLY LOW, DTC P1107 WILL BE SET.

* INFORMATION SENSORS/SWITCHES DESCRIPTION

MANIFOLD ABSOLUTE PRESSURE SENSOR (VIN K) THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS WITH THE KEY ON, ENGINE NOT RUNNING OR AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A VOLTAGE THAT IS LOWER THAN THE POSSIBLE RANGE OF THE MAP SENSOR, DTC P0107 WILL BE SET. A SIGNAL VOLTAGE THAT IS HIGHER THAN THE POSSIBLE RANGE OF THE SENSOR WILL SET DTC P0108. AN INTERMITTENT LOW OR HIGH VOLTAGE WILL SET DTC P1107 OR P1106 RESPECTIVELY.

MANIFOLD ABSOLUTE PRESSURE SENSOR (VIN 1) THE MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR RESPONDS TO CHANGES IN INTAKE MANIFOLD PRESSURE. THE PCM SUPPLIES A 5 VOLT REFERENCE AND A GROUND FOR THE MAP SENSOR. THE MAP SENSOR PROVIDES A SIGNAL TO THE PCM RELATIVE TO PRESSURE CHANGES IN THE MANIFOLD. WITH THE KEY ON, ENGINE NOT RUNNING, THE MAP SENSOR SIGNAL VOLTAGE TO THE PCM VARIES BETWEEN 1.5 TO 2.5 VOLTS. WITH THE ENGINE RUNNING, THE MAP SENSOR VOLTAGE TO THE PCM VARIES FROM BELOW 2 VOLTS AT IDLE (LOW MANIFOLD ABSOLUTE PRESSURE - HIGH VACUUM) TO ABOVE 4 VOLTS AT WIDE-OPEN THROTTLE (HIGH MANIFOLD ABSOLUTE PRESSURE - LOW VACUUM). THE PCM MONITORS THE MAP SIGNALS FOR VOLTAGES OUTSIDE THE NORMAL RANGE OF THE MAP SENSOR. IF THE PCM DETECTS A VOLTAGE THAT IS LOWER THAN THE POSSIBLE RANGE OF THE MAP SENSOR, DTC P0107 WILL BE SET. A SIGNAL VOLTAGE THAT IS HIGHER THAN THE POSSIBLE RANGE OF THE SENSOR WILL SET DTC P0108. AN INTERMITTENT LOW OR HIGH VOLTAGE WILL SET DTC P1107 OR P1106 RESPECTIVELY.

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