Diagnose check engine light. Stored code p2187, p0171, P0174 for system running lean. Smoked intake for vacuum leaks and none found. Found engine vacuum in crankcase due to failed positive crankcase ventilation valve. Crankcase ventilation valve will need to be replaced.
PCV Valve: https://amzn.to/2IznkiY
Crank Case Breather: https://amzn.to/2IznkiY
Engine light is on with fuel trim fault codes and there is an engine knocking noise at times.
Average Reported Mileage: 69772
Tests Procedures: 1. Check for excess crankcase vacuum. Remove the dipstick and connect a vacuum gauge.
2. If vacuum is found, then the pressure regulator valve for the crankcase has failed. See related documents for a picture of the location. Read bulletin LI01.20-P-046639.
3. If no issues are found, then inspect purge valve for being stuck open per bulletin LI47.30-P-049162.
4. Also check for leaking intake per bulletin T-B-09.20/27b.
5. Read bulletin LI09.20-P-061233 and the attached photos for locations of leaks.
6. Verify all recalls and campaigns have been performed.
7. Inspect for incorrect or blocked air filters.
Tech Tips: The pressure regulator valve prevents a vacuum -50 mbar from building up in the crankcase due to the intake manifold vacuum when the gases are extracted from the crankcase. When the crankcase pressure regulator fails, engine oil can get sucked into the combustion chamber.