Suzuki Grand Vitara 2011 Manual page 445

Step
4 INJECTOR RETURN FLOW BALANCE CHECK:
• Allow the engine to heat up to a coolant temperature of >
80 °C, 176 °F.
• Switch OFF the ignition.
• Protect the upper engine edges with rags (mainly around
the injectors).
• Disconnect the injector return pipes.
• Connect special tool (09912 – 96540) to injector.
• Start the engine and let it idle.
• Disconnect the fuel pressure regulator.
• Start the ignition and perform a starting sequence
(activate the starter motor for 5 seconds),
• The flow of fuel on the return is normally very weak.
Otherwise, replace the injector.
• Clear the fault caused by the disconnection of the fuel
flow actuator.
• Refit the injector fuel return pipes after checking that the
seals and pipes are in good condition.
• If this is not the case, replace the injector fuel return
pipes.
• Confirm the repairs by means of a road test.
Special tool
(A): 09912–96540
Is there in good condition?
5 INJECTOR NOZZLE SEALING TEST:
• Check the level and condition of the engine oil:
• If there is pollution via the diesel fuel, the injector nozzle
which is leaking will be "greasy".
• Disconnect the preheating relay.
Check that this is not caused by rising engine oil by checking
the engine compression values.
Check the condition of the heater plug: this must not be
humid. If this is the case, change the defective injector.
If the compression values are in order, locate the faulty
injector by examining the condition of the cylinders and the
pistons via the heater plug wells (greasy cylinder,
overheating, starting to disintegrate, etc.).
If the cylinder-piston examination is not conclusive, remove
the injectors and change the one with the "greasy" nozzle.
NOTE
Before replacing an injector, check for the
presence and conformity of its sealing washer
(refer to "Table 5: Poor Performance with Smoke:
For Diesel Engine Model").
Is there in good condition?
Engine General Information and Diagnosis: For Diesel Engine Model 1A-376
Action Yes
Go to Step 5.
Fuel injector correct.
No
Repair as necessary.
Repair as necessary.