There are many causes for what may seem like a turbocharger related problem, and most can be solved without replacing the turbocharger. Please click on a symptom below to see what some of the most common causes may be. If your turbocharger shows no signs of damage and the center cartridge does not have excessive play back and forth or in and out, and you have checked and/or corrected the most common causes listed below, you may want to have a qualified mechanic check your system before replacing the turbocharger. However, if the turbocharger has failed, you may want to take the time to find out why it failed and correct the problem before installing a new one, otherwise the new one will fail sooner than later.
Click on any of the symptoms to display the most common causes.
Engine Lacks Power
- Dirty air cleaner element
- Collapsed or restricted air pipe before turbocharger
- Restricted or damaged crossover pipe, turbocharger to inlet manifold
- Foreign object between air cleaner and turbocharger
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Inlet manifold cracked, gaskets loose or missing, connections loose
- Exhaust manifold cracked
- Exhaust manifold gasket cracked, burned, blown or missing
- Turbine housing damaged or restricted
- Turbine wheel worn or damaged
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Excessive carbon build-up on compressor housing
- Fuel pump malfunction
- Worn or damaged injector
- Engine valve timing incorrect
- Burned engine valve
- Worn engine piston ring
- Burned engine piston
- Oil bath air cleaner restricted, dirty and/or wrong oil viscosity
- Boost control malfunction, wastegate and/or VNT and/or EMS
Black Smoke
- Dirty air cleaner element
- Collapsed or restricted air pipe before turbocharger
- Restricted or damaged crossover pipe, turbocharger to inlet manifold
- Foreign object between air cleaner and turbocharger
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Inlet manifold cracked, gaskets loose or missing, connections loose
- Exhaust manifold cracked
- Exhaust manifold gasket cracked, burned, blown or missing
- Turbine housing damaged or restricted
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Excessive carbon build-up on compressor housing
- Fuel pump malfunction
- Worn or damaged injector
- Engine valve timing incorrect
- Burned engine valve
- Worn engine piston ring
- Burned engine piston
- Oil bath air cleaner restricted, dirty and/or wrong oil viscosity
- Boost control malfunction, wastegate and/or VNT and/or EMS
Blue Smoke
- Dirty air cleaner element
- Collapsed or restricted air pipe before turbocharger
- Turbocharger flanges, clamps, or bolts loose
- Inlet manifold cracked, gaskets loose or missing, connections loose
- Excessive build-up behind turbine wheel
- Excessive carbon build-up on compressor housing
- Excessive oil used during engine prelube
- Excessive engine idle
- Coked or sludged bearing housing
- Oil filter plugged
- Oil bath air cleaner restricted, dirty and/or wrong oil viscosity
- Boost control malfunction, wastegate and/or VNT and/or EMS
- Turbocharger seal leakage
Excessive Noise
- Dirty air cleaner element
- Air cleaner element missing, leaking, or loose connections to turbocharger
- Collapsed or restricted air pipe before turbocharger
- Restricted or damaged crossover pipe, turbocharger to inlet manifold
- Foreign object between air cleaner and turbocharger
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Inlet manifold cracked, gaskets loose or missing, connections loose
- Exhaust manifold cracked
- Exhaust manifold gasket cracked, burned, blown or missing
- Restricted exhaust system
- Turbine housing damaged or restricted
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Excessive carbon build-up on compressor housing
- Oil bath air cleaner restricted, dirty and/or wrong oil viscosity
- Boost control malfunction, wastegate and/or VNT and/or EMS
Excessive Oil Consumption
- Plugged crankcase breather
- Turbocharger flanges, clamps, or bolts loose
- Restricted oil drain line
- Worn journal bearing
- Excessive engine idle
- Coked or sludged bearing housing
- Oil filter plugged
- Oil bath air cleaner restricted, dirty and/or wrong oil viscosity
- Boost control malfunction, wastegate and/or VNT and/or EMS
- Turbocharger seal leakage
Excessive Oil Compressor End
- Dirty air cleaner element
- Plugged crankcase breather
- Collapsed or restricted air pipe before turbocharger
- Restricted or damaged crossover pipe, turbocharger to inlet manifold
- Foreign object between air cleaner and turbocharger
- Turbocharger flanges, clamps, or bolts loose
- Inlet manifold cracked, gaskets loose or missing, connections loose
- Restricted oil feed line
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Excessive engine idle
- Oil filter plugged
- Oil bath air cleaner restricted, dirty and/or wrong oil viscosity
- Boost control malfunction, wastegate and/or VNT and/or EMS
- Turbocharger seal leakage
Excessive Oil Turbine End
- Plugged crankcase breather
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Restricted oil feed line
- Restricted oil drain line
- Worn journal bearing
- Excessive carbon build-up on compressor housing
- Excessive oil used during engine prelube
- Excessive engine idle
- Coked or sludged bearing housing
- Oil filter plugged
- Boost control malfunction, wastegate and/or VNT and/or EMS
- Turbocharger seal leakage
Wheels and/or Center Cartridge Not Spinning Freely
- Air cleaner element missing, leaking, or loose connections to turbocharger
- Foreign object between air cleaner and turbocharger
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Oil lag at start-up
- Insufficient lubrication
- Lubricating oil contaminated
- Improper lubricating oil
- Restricted oil feed line
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Excessive carbon build-up on compressor housing
- Leaking oil feed line
- Coked or sludged bearing housing
- Oil filter plugged
Excessive Play Center Cartridge
- Foreign object between air cleaner and turbocharger
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Oil lag at start-up
- Insufficient lubrication
- Lubricating oil contaminated
- Improper lubricating oil
- Restricted oil feed line
- Worn journal bearing
- Leaking oil feed line
- Oil pump malfunction
- Oil filter plugged
- Too fast acceleration at initial start
- Too little warm-up time
- Boost control malfunction, wastegate and/or VNT and/or EMS
Damaged Compressor Wheel
- Air cleaner element missing, leaking, or loose connections to turbocharger
- Foreign object between air cleaner and turbocharger
- Turbocharger flanges, clamps, or bolts loose
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Too fast acceleration at initial start
- Too little warm-up time
- Oil filter plugged
- Boost control malfunction, wastegate and/or VNT and/or EMS
Damaged Turbine Wheel
- Foreign object in exhaust system
- Turbocharger flanges, clamps, or bolts loose
- Turbine housing damaged or restricted
- Worn journal bearing
- Excessive build-up behind turbine wheel
- Excessive carbon build-up on compressor housing
- Coked or sludged bearing housing
- Oil filter plugged
- Boost control malfunction, wastegate and/or VNT and/or EMS
Please note this troubleshooting guide is provided for your technical reference and is not an authorization for repair nor is it meant to be a complete guide to turbo diagnostics or a replacement to common sense.