Tech Tip: Infiniti EVAP Leak DTC Diagnosis – DTCs: P0440/P0442/P0455/P0456/P1440/P1456 – UnderhoodService

Tech Tip: Infiniti EVAP Leak DTC Diagnosis – DTCs: P0440/P0442/P0455/P0456/P1440/P1456

Applied Vehicles: 1998 and later Infiniti ­vehicles with an EVAP service port.

DTCs: P0440, P0442, P0455, P0456, P1440 and P1456

If one or more of the DTCs listed above related to EVAP system leaks is found stored in Self Diagnosis, use the Repair Flow Chart shown in Fig. 1. Use the EVAP system diagram (Fig. 2) for reference.

This Service Procedure can be used in addition to the procedure(s) outlined in the applicable service manual, and other bulletins applicable to specific EVAP leak DTCs when necessary.

If a smoke (leak detection) machine is available and preferred, the Repair Flow Chart can still be used. This tool would be used in place of watching for a pressure drop and spraying with soapy water.

Caution: Use Essential Tool J-42909 or equivalent to pressurize the EVAP system. Do not pressurize over the amount specified in the applicable service manual. Do not use shop air pressure.

Note: If one or more EVAP system DTC(s) not related to EVAP leaks is/are found stored in Self Diagnosis, this bulletin does not apply. Refer to ASIST and the appropriate service manual for diagnostic procedure(s) as needed.

Courtesy of ALLDATA.

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