EVAP Emission Control System Operation
- Disconnect purge control vacuum hose with Red stripe from throttle body. See Fig 1
. Connect vacuum pump to purge control vacuum hose. Install plug on vacuum hose fitting on throttle body where purge control vacuum hose was connected.
- Apply 16 in. Hg vacuum to purge control vacuum hose. Start engine and maintain engine speed at 3000 RPM.
- With engine coolant temperature of 104°F (40°C) or less, vacuum should be maintained. With engine coolant temperature of 176°F (80°C) or more, vacuum should not be maintained.
- Remove vacuum pump. Remove plug and reconnect purge control vacuum hose on throttle body. Disconnect purge air hose from air intake hose. See Fig 2
. Connect vacuum pump to purge air hose.
- Install plug on fitting for purge air hose on air intake hose. Start engine and allow engine to idle. Apply 16 in. Hg vacuum to purge air hose.
- Suddenly increase engine speed with engine coolant temperature of 176°F (80°C) or more. Vacuum should not be maintained. Shut engine off. Remove vacuum pump and reinstall purge air hose.
- To check purge vacuum supply at throttle body, disconnect purge control vacuum hose with Red stripe from throttle body. See Fig 1
.
- Connect vacuum gauge on throttle body where purge control vacuum hose was connected. Start engine. Increase engine speed and note vacuum reading. Vacuum should remain constant regardless of engine speed.
- If vacuum remains constant regardless of engine speed, vacuum supply is okay. If no vacuum exists or vacuum varies, check for restricted vacuum port on throttle body. Shut engine off. Remove vacuum gauge and reinstall purge control vacuum hose.
Courtesy of CHRYSLER CORP.
Courtesy of CHRYSLER CORP.