S8 - Check EGR Vacuum

- Disconnect vacuum line at EGR valve, and plug the vacuum line.

- Start engine.

NOTE: When verifying drive symptom, a Diagnostic Trouble Code (DTC) may be stored in memory; erase Continuous Memory after performing this procedure. Clearing Diagnostic Trouble Codes

- For Drive Symptom: Was drive symptom eliminated?

- For No Start: Does engine start?

Yes -- Go to DL50. DL50 - Code 336 or 337: Check For EVR Malfunction

No -- Go to S9. S9 - Check EGR Valve