CAUTION / NOTICE / HINT
Tech Tips
The diagnosis flowchart is for lack of power due to turbocharger factors.
If symptom-specific diagnosis indicates a turbocharger related problem, check using this flowchart.
PROCEDURE
CHECK TURBOCHARGER SUB-ASSEMBLY
Check that no soot or oil adheres to the turbocharger sub-assembly connectors.
Tech Tips
If adhering soot or an oil leak exists, air leaking at that position may be the cause of the lack of boost pressure.
| Result | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| B |
|
CHECK EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY Click here |
| C |
|
CHECK TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |
| D |
|
REPLACE COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY Click here |
| E |
|
REPLACE GASKET |
| A |
|
CHECK COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY (TURBINE SHAFT)
Check that the turbine shaft rotates smoothly, without catching.
Check for loose turbine mounting nuts and for axial play in the turbine shaft.
Tech Tips
If the turbine shaft catches or if there no play or excessive play, it could indicate poor sliding due to seal damage due to seizing or a deposit build-up.
| Standard value |
|---|
| 0.10 mm (0.00394 in.) or less |
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
CHECK COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY Click here |
| A |
|
CHECK WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY
Use a vacuum pump to apply -35 +/-4.0 kPa (-5.08 +/-0.58 psi) negative pressure to the diaphragm chamber and check that the waste gate valve seats.
Note
Do not apply a negative pressure of -65 kPa (-9.43 psi) or more to the waste gate valve actuator with bracket assembly, as doing so may damage the diaphragm.
| Standard |
|---|
| Waste gate valve seats without a gap |
| Result | ||||||||
|---|---|---|---|---|---|---|---|---|
|
| B |
|
CHECK WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY Click here |
| C |
|
CHECK WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY (OPERATION CHECK) Click here |
| A |
|
CHECK WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY
Check for play in the waste gate valve and waste gate valve link.
| Standard |
|---|
| Play exists |
Tech Tips
Some play is required as the waste gate valve link slides. If no play exists, the valve is determined to be stuck.
Check for gaps at the waste gate valve contact surface due to scratches, deformation or wear.
| Standard |
|---|
| 0.50 mm (0.0197 in.) or less |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |
| OK |
|
CHECK AIR BY-PASS VALVE ASSEMBLY
Inspect the air by-pass valve assembly, referring to On-vehicle Inspection for Air by-pass Valve Assembly.
Inspect the air by-pass valve assembly, referring to Inspection for Air by-pass Valve Assembly.
Check for accumulated deposits, deformation and wear on the air by-pass valve assembly contact surfaces (air by-pass valve side and compressor housing side).
Tech Tips
A problem with the air by-pass valve assembly contact surfaces may allow air to leak from the damaged position.
| Standard |
|---|
| 0.50 mm (0.0197 in.) or less wear on the contact surface |
| Result | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||
| A |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| B |
|
REPLACE COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY Click here |
| C |
|
REPLACE AIR BY-PASS VALVE ASSEMBLY Click here |
CHECK WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY
Check the waste gate valve actuator pin for wear.
| Standard |
|---|
| 0.50 mm (0.0197 in.) or less |
Tech Tips
If the wear on the waste gate valve actuator pin does not exceed the standard (no problem with waste gate valve actuator with bracket assembly), the cause may be wear of the waste gate valve link or cracks in the bushing. Replace the turbine housing with valve sub-assembly.
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |
| NG |
|
REPLACE WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY Click here |
CHECK WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY (OPERATION CHECK)
Move the waste gate valve actuator link and rod by hand to check that they move smoothly (do not stick).
Tech Tips
If the waste gate valve actuator link and rod move smoothly by hand but the valve does not operate when a negative pressure is applied, there may be damage to the diaphragm, etc. inside the waste gate valve actuator.
| Result | |||||||
|---|---|---|---|---|---|---|---|
|
| A |
|
REPLACE WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY Click here |
| B |
|
REPLACE TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |
CHECK COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY
Check for interference between the turbine wheel and the turbine housing.
Tech Tips
If interference exists between the turbine wheel and turbine housing, replace the compressor housing with bearing sub-assembly and turbine housing with valve sub-assembly as a set.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
REPLACE COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY Click here |
| B |
|
REPLACE COMPRESSOR HOUSING WITH BEARING SUB-ASSEMBLY AND TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |
CHECK EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY
Check for deformation or cracks in the mounting surfaces on the exhaust manifold converter sub-assembly and the turbocharger sub-assembly.
Tech Tips
Deformation or cracks on a mounting surface may allow exhaust gas to leak from the damaged position.
| Standard |
|---|
| No deformation or cracks on a mounting surface |
| Result | ||||||||
|---|---|---|---|---|---|---|---|---|
|
| B |
|
REPLACE EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY Click here |
| C |
|
REPLACE TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |
| A |
|
REPLACE EXHAUST PIPE CLAMP AND GASKET
Replace the exhaust pipe clamp and the gasket.
| Result | ||
|---|---|---|
|
| NEXT |
|
PERFORM SIMULATION TEST
Check that the abnormal state has disappeared.
| Result | ||
|---|---|---|
|
| NEXT |
|
END |
CHECK TURBINE HOUSING WITH VALVE SUB-ASSEMBLY
Check that the bushing of the turbine housing waste gate valve link is free of cracks and the play does not exceed 0.5 mm.
| Standard |
|---|
| No cracks and play does not exceed 0.50 mm (0.0197 in.) |
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
REPLACE TURBINE HOUSING WITH VALVE SUB-ASSEMBLY Click here |