Toyota Tundra 5.7 3UR-FE 89663-0C601_ST1_E2_SAP OFF Firmware

89663-0C601_ST1_E2_SAP OFF REMOVE CONNECTORS SV 5000 p. is a modified engine-control calibration cataloged for the Toyota Tundra 5.7-liter 3UR-FE V8. Its clearest named change is SAP OFF, which denotes a modification to the secondary air injection system’s operation or diagnostics. The related catalog identifier is 89663-0C601.

What SAP OFF means

The engine control module manages fuel, ignition and emissions-related functions using inputs from engine sensors. On a vehicle equipped with secondary air injection, it also commands the system that pumps fresh air into the exhaust during a cold start. That added oxygen helps the catalytic converters reach effective operating temperature sooner.

The SAP OFF label indicates that this modified variant is intended to suppress secondary air injection functionality, related fault monitoring, or both. The filename alone does not establish the exact strategy. In practice, changes to this system can affect cold-start emissions and may affect emissions compliance or inspection results.

Reading the variant labels

ST1 identifies the file as a Stage 1 variant, commonly used to describe a performance-oriented calibration. The label does not specify its power output or the exact fuel and ignition changes. E2 is another variant designation, but its precise meaning is not established by the catalog name.

REMOVE CONNECTORS and SV 5000 p. are also attached to the modified filename. The first indicates a connector-related condition, while the second appears to name a setting or characteristic. The filename does not identify the connectors or define the setting well enough to describe either more precisely.

The shorter 89663-0C601 entry identifies the underlying calibration family. The Stage 1, E2, SAP OFF and other modification labels belong to the longer variant, not automatically to every file carrying the base identifier.