Troubleshooting¶

Hint

Before troubleshooting the turbocharger, first check the engine itself. (Valve clearance, engine compression, ignition timing etc.)

Insufficient acceleration, lack of power or excessive fuel consumption¶

Possible cause	Check procedure and correction method
1. Turbocharging pressure too low	Check turbocharging pressure. (See Turbocharger) Turbocharging pressure: 0.50 – 0.83 kg/cm² (7.1 – 11.8 psi, 49 – 81 kPa) If the pressure is below specification, begin diagnosis from item 2.
2. Restricted intake system	Check intake air system, and repair or replace parts as necessary. (See Turbocharger › Removal of turbocharger)
3. Leak in intake air system	Check intake air system, and repair or replace parts as necessary. (See Turbocharger › Removal of turbocharger)
4. Restricted exhaust system	Check exhaust system, and repair or replace parts as necessary. (See Turbocharger › Removal of turbocharger)
5. Leak in exhaust system	Check exhaust system, and repair or replace parts as necessary. (See Turbocharger › Removal of turbocharger)
6. Erratic turbocharger operation	Check rotation of impeller wheel. If it does not turn or turn with a heavy drag, replace the turbocharger assembly. Check axial and radial plays of impeller wheel. (See Turbocharger › Inspection of turbocharger) Axial play: 0.13 mm (0.0051 in.) or less Radial play: 0.18 mm (0.0071 in.) or less If not within specification, replace the turbocharger assembly.

Abnormal noise¶

Possible cause	Check procedure and correction method
1. Turbocharging heat insulator resonance	Check for loose, improperly installed or deformed insulator mount bolts, and repair or replace as necessary.
2. Exhaust pipe leaking or vibrating	Check for deformed exhaust pipe, loose mount bolts or damaged gasket, and repair or replace as necessary.
3. Erratic turbocharger operation	Refer to item 6 of Insufficient acceleration, lack of power or excessive fuel consumption.

Excessive oil consumption or white exhaust¶

Possible cause

Check procedure and correction method

1. Faulty turbocharger seal

Check for oil leakage in exhaust system.

Remove the turbine elbow from the turbocharger and check for excessive carbon deposits on the turbine wheel. Excessive carbon deposits indicate a faulty turbocharger.

Check for oil leakage in intake air system.

Check for axial and radial plays in impeller wheel, and replace the turbocharger if necessary. (See Turbocharger › Inspection of turbocharger)

Axial play: 0.13 mm (0.0051 in.) or less
Radial play: 0.18 mm (0.0071 in.) or less
Notice: There is some oil mist from the PCV in the blowby gas so care must be taken not to diagnosis this as oil leakage from the turbocharger.