EVAP Leak Detection Pump Pressure Switch Condition (Chrysler)
What does P1494 mean?
The P1494 code means the vehicle's onboard diagnostic system has detected: EVAP Leak Detection Pump Pressure Switch Condition (Chrysler). This is a low severity code.
Common Symptoms
- Check Engine Light illuminated
- No drivability symptoms
- EVAP readiness monitor will not complete
- Failed emissions inspection
- Faint fuel smell possible
Probable Causes (Ranked by Likelihood)
- Faulty EVAP leak detection pump Very High
- Cracked or disconnected vacuum hose to the pump High
- Stuck pressure switch inside the pump assembly High
- Corroded connector at the leak detection pump Moderate
- Large EVAP system leak overriding the pump Low
Step-by-Step Diagnostic Procedure
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Locate the leak detection pump near the fuel tank and inspect the electrical connector for corrosion.
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Check all vacuum hoses connected to the pump for cracks, kinks, or disconnections.
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Use a scan tool to activate the leak detection pump and monitor the pressure switch state.
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Test the pump by applying 12V directly and listening for pumping sounds.
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Perform a smoke test on the EVAP system to rule out a major leak.
Frequently Asked Questions
What is the leak detection pump pressure switch?
The leak detection pump has an internal pressure switch that tells the PCM when the EVAP system has been pressurized to the correct level. If the switch does not change state, the PCM cannot complete the leak test.
Where is the leak detection pump?
On most Chrysler, Dodge, and Jeep vehicles, it is mounted on or near the charcoal canister, which is usually located near the fuel tank under the vehicle.
Can the pressure switch be replaced separately?
On most applications, the pressure switch is integral to the pump assembly and cannot be replaced independently. The entire leak detection pump must be replaced.