Grand Cherokee 4WD V8-4.7L VIN N (2000)
Camshaft Position Sensor: All Technical Service Bulletins
Engine - CMP Defect/Poor Engine Performance
NUMBER: 08-22-00 Rev A
GROUP: Electrical
DATE: Aug. 4, 2000
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 08-22-00, DATED JUNE 16, 2000, WHICH SHOULD BE REMOVED
FROM YOUR FILES. ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS** AND INCLUDE A REVISED PART NUMBER
SUBJECT:
4.7L Camshaft Position Sensor Contacts Tone Wheel
OVERVIEW:
This bulletin involves the measurement and possible adjustment to the 4.7L camshaft position sensor.
MODELS:
2000
(AN)
Dakota
2000
(DN)
Durango
2000
(WJ)
Grand Cherokee
NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 4.7L ENGINE. ENGINES BUILT WITH AN ENGINE DATE CODE FROM
NOV. 01, 1999 (JULIAN DATE OF 3059) TO NOV. 03, 1999 (JULIAN DATE OF 3079) MAY BE EFFECTED. THE ENGINE BUILD DATE
CAN BE FOUND ON THE ENGINE BAR CODE LABEL, AFFIXED TO THE OIL FILL HOUSING.
SYMPTOM/CONDITION:
The customer may notice a lower than expected engine performance due to a possible loss or intermittent loss of the camshaft position sensor (CMP)
signal. The loss of the CMP signal may be the result of the CMP physically contacting the tone wheel. If this occurs, the internal electronic circuitry of
the CMP may become damaged. This condition may cause the illumination of the Malfunction Indicator Lamp (MIL).
The camshaft position sensor may make contact with the tone wheel because the pad on the cylinder head, which the CMP attaches to, was
over-machined.
NOTE:
THE POSSIBILITY OF THIS CONDITION OCCURRING IS LIMITED TO A VERY SMALL QUANTITY OF 4.7L ENGINES. VERIFY THE
ENGINE BUILD DATE.
Most of the suspect engines were inspected and repaired by the engine assembly plant. If required, a select fit shim was installed between the CMP
sensor and the cylinder head pad, and around the CMP sensor attaching bolt. The shim may have been glued in place to either the pad on the cylinder
head or to the mounting tang on the camshaft position sensor.
A technician making repairs in the area of the CMP sensor may overlook or lose the previously installed shim. This may then cause the camshaft position
sensor to contact the tone wheel when the CMP sensor is reinstalled or replaced.
DIAGNOSIS:
1.
Using the DRB III(R) and the respective vehicle 2000 model year Powertrain Diagnostic Procedures manual, determine if the driveability or MIL
condition is caused by a loss of the camshaft position sensor signal.
2.
If the problem is determined to be the cam position sensor, then inspect the Engine Bar Code Label affixed to the oil fill housing. The label may be
white, pink, or green in color.
3.
From the Engine Bar Code Label, read the top line of alpha-numeric numbers (the engine identification number) to determine if the engine in
question falls on or within the Julian day and calender year
The engine identification number is in the following format: TPCEKDDDYSSSSS
T = Traceability number (T = T)
P = An internal code to be used at the discretion of the engine plant.
C = An internal code to be used at the discretion of the engine plant.
EK = Mack Avenue Engine Plant
DDD = Julian Day of engine build (0 to 365 days)
Y = Calender year of engine build (0 to 9. A number 9 = the year 1999)
