P0170
Fuel Injection System Function P0170ON BOARD DIAGNOSIS LOGIC
With Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the theoretical mixture ratio based on the mixture ratio feedback signal from the front oxygen sensor. The ECM calculates the necessary compensation to correct the offset between the actual and the theoretical ratios. In case the amount of the compensation value is extremely large, the ECM judges the condition as the fuel system malfunction and lights up the MIL (2 trip detection logic).
DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE (Overall)
WITH CONSULT
(1) Start engine and warm it up sufficiently.
(2) Turn ignition switch "OFF" and wait at least 3 seconds.
(3) Turn ignition switch "ON" and select "SELF-LEARN CONTROL" in "ACTIVE TEST" mode with CONSULT.
(4) Clear the self-learning control coefficient by touching "CLEAR".
(5) Start engine again and run it for at least 10 minutes at idle speed.
The DTC should be detected at this stage, if a malfunction exists.
(6) If it is difficult to start engine at step 5, the fuel injection system has a malfunction, too.
OR
WITH NO TOOLS
(1) Start engine and warm it up sufficiently.
(2) Turn ignition switch "OFF" and wait at least 3 seconds.
(3) Disconnect mass air flow sensor harness connector. Then restart and run engine for at least 3 seconds at idle speed.
(4) Stop engine and reconnect mass air flow sensor harness connection
(5) Perform Diagnostic Test Mode II (Self-diagnostic results) with ECM. Make sure DTC 12 is detected.
(6) Erase the DTC 12 by changing from Diagnostic Test Mode II to Diagnostic Test Mode I.
(7) Perform Diagnostic Test Mode II (Self-diagnostic results) with ECM. Make sure DTC 55 is detected.
(8) Start engine again and run it for at least 10 minutes at idle speed.
The DTC 76 should be detected at this stage, if a malfunction exists.
(9) If it is difficult to start engine at step 8, the fuel injection system has a malfunction.
WIRING DIAGRAM
DIAGNOSTIC PROCEDURE
