Vacuum At EGR Valve
- Install "T" fitting at EGR valve and connect vacuum gauge. With engine running at idle and engine coolant temperature above 172°F (78°C), vacuum should be present. If there is, check and adjust EGR linkage as necessary. If no vacuum is present, remove "T" fitting and vacuum gauge. Connect vacuum hose to EGR valve.
- Disconnect vacuum inlet hose at EGR solenoid and install "T" fitting and vacuum gauge. Run engine at idle and check for vacuum. If there is, check EGR solenoid. See EGR SOLENOID in this section. If no vacuum is present, remove "T" fitting and vacuum gauge. Connect vacuum hose to EGR solenoid.
- Disconnect vacuum outlet hose "B" from vacuum regulator and install "T" fitting and vacuum gauge. Run engine at idle and check for vacuum. If vacuum is okay, replace faulty vacuum hoses and/or delay valve and /or vacuum damper as necessary. Recheck system operation.
- If vacuum is not okay, remove "T" fitting and vacuum gauge. Connect vacuum hose "B" to EGR vacuum regulator. Disconnect vacuum inlet hose "A" from vacuum regulator and install "T" fitting and vacuum gauge. Run engine at idle and check for vacuum. If vacuum is okay, replace vacuum regulator. Check system operation.
- If no vacuum is present, remove "T" fitting and vacuum gauge. Connect vacuum inlet hose "A". Disconnect vacuum hose at vacuum pump outlet on camshaft cover. Connect vacuum gauge to vacuum pump outlet. Run engine at idle and check for vacuum.
- If vacuum is okay, replace vacuum hose between vacuum pump and vacuum regulator on injection pump. Check system operation. If no vacuum is present, replace vacuum pump. Check system operation.