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Evaporative System Test

Evaporative system test outline
- To verify the problem has been fixed properly after repairs, Drive Mode 4 or evaporative system test must be performed.
- The evaporative system test, which can substitute for Drive Mode 4 as an evaporative system repair confirmation method, can be conducted while operating the NGS tester at idle instead of actually driving the vehicle.

Evaporative system test description
- The evaporative system test finds gas leakage in the system using the PCM to monitor negative pressure changes in the system. This test starts after sending an on-demand test signal from the NGS tester to the PCM. The PCM controls CDCV and PRGV operation and stores FTP values as follows:
1. The PCM commands the PRGV to open, which relieves the negative pressure in the evaporative system to the specified level. Then PCM commands the CDCV to close. The purpose of each valve's operation is as follows:
1. Opening the PRGV lets the negative pressure from the intake manifold into the evaporative line.
2. Closing the CDCV shuts off the evaporative line from the outside atmosphere.

2. When negative pressure in the evaporative system has reached the specified level or negative pressure relief has gone on for the specified amount of time, the PCM commands the PRGV to close and seals the system. This is to seal the evaporative system and maintain negative pressure.







3. The PCM will maintain this sealed condition for about 33 seconds while storing the FTP1 and FTP2 at each pre-set time interval.
- You can confirm whether any evaporative gas leakage occurred or not by reading the test results.

Evaporative system malfunction judgment
- The NGS tester calculates the stored FTP values and displays the results as follows:
1. Large leak results (DTC P0455) - FTP1
2. Small leak results (DTC P0442) - A

Evaporative system test procedure

NOTE: This is an alternative procedure for the dealers that can not drive the vehicle in the OBD-II Drive Mode 4.




1. Connect the SST (NGS tester) to DLC-2.
2. Select NEW GENERATION STAR SETUP from main menu.
3. Select ENGLISH / METRIC UNIT SELECTION.
4. Press SI key (#4) to change units to the metric system.
5. Press CANCEL two times to go back to the main menu.
6. Access and record the BARO, ECT, FLT V and IAT PIDs.

Specifications:




7. Verify all PIDs are within specification.

NOTE:
- Best results are achieved when all PID values reach specification.
- If the test must run without PID values at the specified level, reduce the fuel temperature by cooling the fuel tank for 1 hour with a fan.

8. Start the engine and race it at 3,500 rpm for 200 seconds to warm it up completely.
9. Press CANCEL two times.
10. Select DIAGNOSTIC SUPPORT PROCEDURE and press TRIGGER.
11. Select SINGLE TEST and press TRIGGER.
12. Select EVAP LEAK TEST and press TRIGGER.
13. Press TRIGGER one more time to start the test.
14. Verify the engine speed increases to 2,000 rpm and wait for 1 minute.
15. Depress the accelerator pedal to end the test condition.
16. Access and record FTP1SV and FTP2SV PIDs.

Large Leak Specification:




17. Verify that FTP1SV PID are within the specification in the table according to the BARO and ECT PID values recorded in Step 6.
- If FTP1SV PID is within specification, go to next step.
- If FTP1SV PID is not within specification and PID values at Step 6 were within specification before testing, the EVAP system still has large leak. Repeat DTC P0455 troubleshooting.
- If FTP1SV PID is not within specification and PID values at Step 6 were not within specification before testing, repeat the test after all PID values at Step 6 are within specification.

18. Subtract FTP 1SV from FTP 2SV.

NOTE:
- When a larger negative number is subtracted from a smaller negative number, the result is a positive number. (i.e. FTP2SV - FTP1SV = -0.4 - (-0.6) - 0.4 + 0.6 = 0.2)




19. Verify that (FTP2SV - FTP1SV) value is within the specification in the table according to the BARO and ECT PID values recorded in Step 6.
- If (FTP2SV - FTP1SV) is within specification, the repair is complete. Clear pending or stored DTC.
- If (FTP2SV - FTP1SV) is not within specification and PID values at Step 6 were within specification before testing, the EVAP system still has malfunction. Repeat DTC P0442 troubleshooting.
- If (FTP2SV - FTP1SV) is not within specification and PID values at Step 6 were not within specification before testing, repeat the test after all PID values at Step 6 are within specification.

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