Toyota Tundra 4.7 2UZ-FE 89663-0C791_E2_SAP OFF FULL_CVN OK_CRC OK_736kb
A guide to the Toyota Tundra 4.7 2UZ-FE 89663-0C791 engine calibration and its SAP OFF, CVN and CRC labels.
The 89663-0C791_E2_SAP OFF FULL_CVN OK_CRC OK_736kb catalog entry describes a modified engine-control calibration for the Toyota Tundra 4.7-liter 2UZ-FE V8. Its named modification is SAP OFF FULL, indicating that the file is intended to disable the secondary air injection system in the engine-control software.
What the engine controller manages
The Toyota engine control module uses its calibration to manage functions such as fuel delivery, ignition timing and emissions controls. The 89663-0C791 identifier belongs to the engine calibration record shown for this Tundra application. The related catalog entry 89663-0C791 identifies the base calibration, while the longer filename describes the modified variant.
What SAP OFF means in practice
The secondary air injection system supplies fresh air to the exhaust during certain cold-start conditions. This helps the catalytic converters reach effective operating temperature sooner and reduces emissions during warm-up. The engine controller commands the system and monitors its operation.
In the longer filename, SAP OFF FULL labels a modification intended to turn off that system’s software operation. It is a characteristic of the named modified file, not a feature established by the bare 89663-0C791 catalog entry. Disabling an emissions-control system can affect cold-start emissions and may make a vehicle noncompliant with applicable road-use rules.
CVN, CRC and file labels
CVN OK and CRC OK are file labels concerning calibration verification and checksum status. They describe claims attached to this modified variant, not proof of independent verification or compatibility with a particular vehicle. 736kb identifies the stated file size, and E2 is an additional variant label whose precise meaning is not established by the catalog name.