Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
EVAP System
EVAP System Troubleshooting
Special Tools Required
Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000A or equivalent, commercially available
Vacuum/Pressure Gauge, 0-4 inHg 07JAZ-001000B
- EVAP canister purge valve check (open stuck)
-1. Disconnect the vacuum hose (A) from the EVAP canister (B), and connect a vacuum pump/gauge, 0-30 inHg, to the hose.
-2. Start the engine, and let it idle.
NOTE: The engine coolant temperature must be at least 149 deg.F (65 deg.C).Signal Current conditions Values Unit ECT SENSOR 1 Is there vacuum?
YES
Inspect the vacuum hose routing. If OK, replace the EVAP canister purge valve .
NO
Go to step 2.
- EVAP canister purge valve check (closed stuck)
-1. Hold the engine speed at 3000 RPM without load (in P or N) until the radiator fan comes on, then continue to hold the engine speed at 3000 RPM.
Is there vacuum?
YES
Go to step 3.
NO
Inspect the vacuum hose routing. If OK, replace the EVAP canister purge valve .
- EVAP canister check
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Reconnect the vacuum hose to the EVAP canister.
-3. Insert the emergency fuel funnel into the fuel filler neck .
NOTE: The emergency fuel funnel is stored in the trunk tools box.-4. Disconnect the purge air hose (A) from the EVAP canister (B), and connect a T-fitting (C) and a vacuum gauge to the hose as shown.
-5. Start the engine and raise the engine speed to 3000 RPM.
Does vacuum appear on gauge within 1 minute?
YES
Do the EVAP two way valve test . If it is OK, the evaporative emission system is OK.
NO
NO RELATED
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.