XJ-6 L6-4.2L (1983)
Air Flow Meter/Sensor: Technical Service Bulletins
Fuel System - Conditions for CO Adjustment
DATE . . . FEBRUARY, 1985
NUMBER . . . J85/08
MODEL:
XJ6 & XJ-S
SUBJECT:
CO ADJUSTMENT TAMPER PROOFING
KEY POINTS
PROCEDURES AND CON-
DITIONS FOR CO ADJUSTMENT OF
VEHICLES IN SERVICE.
Dealers are reminded that both the air flow meter and EFI electronic control unit CO adjustments are set to Emission specifications
during vehicle production and a tamper-proof plug is fitted to both the air flow meter and the ECU.
If a vehicle is determined to be out of specification, the reason must be determined i.e., incorrect operation of EFI sensors, vacuum
leaks, contaminated crankcase oil, contaminated injectors, fouled spark plugs, plug wires off, restricted catalysts, etc.
If, after thorough checks, the air flow meter is suspect, then it must be replaced. No attempt should be made to adjust the existing air
flow meter.
Replacement air flow meter and ECUs are supplied without the tamper-proof plug being fitted. These units may be adjusted for fuel
mixture. When the CO is correct, the tamperproof plug, ULC 3690, must be permanently installed.
