Usually, loose or bad fuel tank filler cap will trigger these codes. Retighten fuel tank filler cap and clear the code to repair the problem. There are several Nissan service bulletins for this problem if tighten the gas cap does not repair the problem, check for Nissan Service bulletins for your model year.
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How to Fix the DTC P1456 2002 Nissan Altima Sedan?
Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
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What is the Cost to Diagnose the Code?
Labor: 1.0
The cost to diagnose the P1456 2002 Nissan Altima Sedan code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.
When is the Code Detected?
The P1456 code is detected when the EVAP system has a very small leak.
What are Code Possible Symptoms?
Engine Light ON (or Service Engine Soon Warning Light)
A noticeable fuel odor may result from fuel vapor release
What Does the P1456 2002 Nissan Altima Sedan Code Mean?
This diagnosis detects leaks in the Evaporative Emission (EVAP) purge line using engine intake manifold vacuum. If pressure does not increase, the Engine Control Module (ECM) will check for leaks in the line between the fuel tank and EVAP canister purge volume control solenoid valve under the following vacuum test condition.
The vacuum cut valve bypass valve is opened to clear the line between the fuel tank and the EVAP canister purge volume control solenoid valve. The EVAP canister vent control valve will then be closed to shut the EVAP purge line off. The EVAP canister purge volume control solenoid valve is opened to depressurize the EVAP purge line using intake manifold vacuum. After this depressurization is implemented, the EVAP canister purge volume control solenoid valve will be closed.
Most Nissan Models EVAP System Diagram
P1456 2002 Nissan Altima Sedan Code - Evaporative Emission Control System Leak Detected Small Leak