Chapter 13 Exhaust Systems 299 Copyright Goodheart-Willcox Co., Inc. Turbocharger Inspection and Troubleshooting Figure 13-34 lists common turbocharger problems and probable causes. If a defective turbocharger is suspected, always make sure the turbocharger is really at fault. Repairs are sometimes performed on the turbocharger when the real source of the trouble is a restricted air cleaner, a plugged crankcase breather, or deteriorated oil lines. Common symptoms that may indicate turbocharger trouble include: ❑ A lack of engine power. ❑ Black smoke. First-stage turbocharger Second-stage turbocharger Figure 13-33. Two-stage turbocharging utilizes two turbochargers. (Garrett Group, Inc.) Turbocharger Troubleshooting Guide Condition Possible Causes Code Numbers Cause Description by Code Numbers Engine lacks power 1, 4, 5, 6, 7, 8, 9, 10, 11, 18, 20, 21, 22, 25, 26, 27, 28, 29, 30, 37, 38, 39, 40, 41, 42, 43 1. Dirty air cleaner element 2. Plugged crankcase breathers 3. Air cleaner element missing, leaking, not sealing correctly loose connections to turbocharger 4. Collapsed or restricted air tube before turbocharger 5. Restricted damaged crossover pipe, turbocharger to inlet manifold 6. Foreign object between air cleaner and turbocharger 7. Foreign object in exhaust system (from engine, check engine) 8. Turbocharger flanges, clamps, or bolts loose 9. Inlet manifold cracked gaskets loose or missing connections loose 10. Exhaust manifold cracked, burned gaskets loose, blown, or missing 11. Restricted exhaust system 12. Oil lag (oil delay to turbocharger at startup) 13. Insufficient lubrication 14. Lubricating oil contaminated with dirt or other material 15. Improper type lubricating oil used 16. Restricted oil feed line 17. Restricted oil drain line 18. Turbine housing damaged or restricted 19. Turbocharger seal leakage 20. Worn journal bearings 21. Excessive dirt buildup in compressor housing 22. Excessive carbon buildup behind turbine wheel 23. Too fast acceleration at initial start (oil lag) 24. Too little warmup time 25. Fuel pump malfunction 26. Worn or damaged injectors 27. Valve timing 28. Burned valves 29. Worn piston rings 30. Burned pistons 31. Leaking oil feed line 32. Excessive engine pre-oil 33. Excessive engine idle 34. Coked or sludged center housing 35. Oil pump malfunction 36. Oil filter plugged 37. Oil-bath-type air cleaner: • Air inlet screen restricted • Oil viscosity high • Oil pullover • Oil viscosity low • Dirty air cleaner 38. Actuator damaged or defective 39. Waste gate binding 40. Electronic control module or connector(s) defective 41. Waste gate actuator solenoid or connector defective 42. EGR valve defective 43. Alternator voltage incorrect 44. Engine shut off without adequate cool down time 45. Leaking valve guide seals 46. Low oil level Black smoke 1, 4, 5, 6, 7, 8, 9, 10, 11, 18, 20, 21, 22, 25, 26, 27, 28, 29, 30, 37, 38, 39, 40, 41, 43 Blue smoke 1, 2, 4, 6, 8, 9, 17, 19, 20, 21, 22, 32, 33, 34, 37, 45 Excessive oil consumption 2, 8, 15, 17, 19, 20, 29, 30, 31, 33, 34, 37, 45 Excessive oil– turbine end 2, 7, 8, 17, 19, 20, 22, 29, 30, 32, 33, 34, 45 Excessive oil– compressor end 1, 2, 4, 5, 6, 8, 19, 20, 21, 29, 30, 33, 34, 45 Insufficient lubrication 8, 12, 14, 15, 16, 23, 24, 31, 34, 35, 36, 44, 46 Oil in exhaust manifold 2, 7, 17, 18, 19, 20, 22, 29, 30, 33, 34, 45 Damaged compressor wheel 3, 4, 6, 8, 12, 15, 16, 20, 21, 23, 24, 31, 34, 35, 36, 44, 46 Damaged turbine wheel 7, 8, 12, 13, 14, 15, 16 18, 20, 22, 23, 24, 25, 28, 30, 31, 34, 35, 36, 44, 46 Drag or bind in rotating assembly 3, 6, 7, 8, 12, 13, 14, 15, 16, 18, 20, 21, 22, 23, 24, 31, 34, 35, 36, 44, 46 Worn bearings, journals, bearing bores 6, 7, 8, 12, 13, 14, 15, 16, 23, 24, 31, 35, 36, 44, 46 Noisy 1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 21, 22, 23, 24, 31, 34, 35, 36, 37, 44, 46 Sludged or coked center housing 2, 11, 13, 14, 15, 17, 18, 24, 31, 35, 36, 44, 46 Figure 13-34. Turbocharger troubleshooting guide. This guide is very useful in diagnosing many turbocharger performance related problems. (Garrett Group, Inc.)