EVAP System Troubleshooting

Special Tools Required
Combination gauge kit (  07YAJ-0010610)
 

Tube joint adapter (  07410-5790501)
 


1.Inspect the No. 16 (7.5A) fuse in the under-dash fuse/relay box.

Is fuse OK?


YES - Go to 2.


NO - Replace the fuse, and recheck.n


2.Disconnect the vacuum hose (A) and connect a vacuum pump/gauge (B) to the hose.

 

3.Start the engine and let it idle.

NOTE: Engine coolant temperature must be below 65°C (149°F).

4.Quickly raise the engine speed to 3,000 rpm (min-1).

Is there vacuum?


YES - Go to 5.


NO - Go to 10.


5.Disconnect the EVAP canister purge valve 2P connector.

6.Quickly raise the engine speed to 3,000 rpm (min-1).

Is there vacuum?


YES - Inspect vacuum hose routing. If OK, replace the EVAP canister purge valve.n


NO - Go to 7.


7.Turn the ignition switch OFF.

8.Disconnect PCM connector B (24P).

9.Check for continuity between EVAP canister purge valve 2P connector terminal No. 2 and body ground.

 

Is there continuity?


YES - Repair short in the wire between the EVAP cansiter purge valve and the PCM (B21).n


NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original  PCM.n


10.Start the engine. Hold the engine at 3,000 rpm (min-1) with no load (in Park or neutral) until the radiator fan comes on, then let it idle.

11.Check for vacuum at the vacuum hose after the starting the engine.

12.Quickly raise the engine speed to 3,000 rpm (min-1).

Is there vacuum?


YES - Go to 23.


NO - Go to 13.


13.Turn the ignition switch OFF.

14.Inspect the vacuum hose rooting.

Is the vacuum hose OK?


YES - Go to 15.


NO - Repair the vacuum hose.n


15.Disconnect the EVAP canister purge valve 2P connector.

16.Turn the ignition switch ON (II).

17.At the harness side, measure voltage between EVAP canister purge valve 2P connector terminals No. 1 and No. 2.

 

Is there any voltage?


YES - Replace the EVAP canister purge valve.n


NO - Go to 18.


18.At the harness side, measure voltage between EVAP canister purge valve 2P connector terminal No. 1 and body ground.

 

Is there battery voltage?


YES - Go to 19


NO - Repair open in the wire between No. 16 (7.5A) fuse in the under-dash fuse/relay box and the EVAP canister purge valve.n


19.Turn the ignition switch OFF.

20.Reconnect the EVAP canister purge valve 2P connector.

21.Turn the ignition switch ON (II).

22.Measure voltage between PCM connector terminal B21 and body ground.

 

Is there battery voltage?


YES - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original  PCM.n


NO - Repair open in the wire between the EVAP canister purge valve and the PCM (B21).n


23.Reconnect the vacuum hose to the EVAP control canister.

24.Remove the fuel fill cap.

25.Disconnect the purge air hose (A) from the EVAP canister and connect the combination gauge kit and tube joint adapter to EVAP canister (B) and connect a vacuum pump (C).

 

26.Start the engine and raise speed to 3,000 rpm (min-1).

Does vacuum appear on gauge within 2 minute?


YES - When vacuum is appear, evaporative emission controls are OK. Check the EVAP two way valve test.n


NO - Replace the EVAP canister.n