CUSTOMER CONCERN The engine idles too high after throttle-body cleaning, and DTC P0507 may return intermittently. CAUSE The throttle-position learned value was not reset after service, leaving the idle control strategy out of calibration. CORRECTION Reset the throttle-position learned value and perform the idle relearn procedure.

CUSTOMER CONCERN Customer states the engine runs rough and enters reduced-power operation. DTC P0121 is stored. CAUSE Throttle-position data and connector-terminal testing confirmed an internal throttle-body position-sensor fault. CORRECTION Remove and replace throttle-body assembly. Perform idle-learn reset, clear DTC P0121 and verify throttle response and normal power.

CUSTOMER CONCERN Customer states the check-engine light is on and engine idle speed is too high. DTC P0507 is stored. CAUSE Idle-speed testing confirmed the idle-air volume adaptation was not completing, leaving engine speed more than 200 rpm above the target value. CORRECTION Perform accelerator-pedal released-position learning, throttle-valve closed-position learning and idle-air volume learning. Clear DTC P0507 and verify normal idle speed.

CUSTOMER CONCERN Customer states the engine will not idle after diagnostic codes were cleared. CAUSE Clearing adaptive memory exposed throttle-plate deposits and removed the learned idle correction values. CORRECTION Remove EFI and ETCS fuses for the specified reset period, clean throttle body and perform throttle-body idle relearn. Verify stable idle operation.