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Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 104

1A-363 Engine General Information and Diagnosis: For Diesel Engine Model

Table 6: Poor Performance without Smoke

S6JB0A1124159

NOTE
In the case of engine overheating to more than 119

°C, 246 °F the computer deliberately limits the fuel

flow (overheating warning light illuminates from 115

°C, 239 °F).

Troubleshooting

Step

Action

Yes

Is the engine running on all cylinders?

Go to Step 2.

Check the injector
operation referring to
“Test 8: Injector
malfunction: For Diesel
Engine Model”.

Check the conformity of the accelerator pedal position
sensor, the brake lamp switch, the boost pressure sensor,
the EGR valve and the inlet throttle valve.

Is there in good condition?

Go to Step 3.

Carry out the required
repairs.

Check the consistency of the signal: of the MAF sensor, of
the ECT sensor and of the engine speed.
Check the connections, the continuity and absence of
interference resistance of the MAF sensor (refer to “DTC
P0100: Mass or Volume Air Flow Circuit: For Diesel Engine
Model” of troubleshooting for 2.DEF: Offset at minimum
threshold.), of the ECT sensor (refer to “DTC P0115: ECT
Circuit: For Diesel Engine Model”), and the engine speed
(refer to “DTC P0016: CKP – CMP Correlation: For Diesel
Engine Model”).

Is there in good condition?

Go to Step 4.

Carry out the required
repairs.

Check the following:
• Diesel filter not clogged (for the test, refer to “DTC P0089:

Fuel Flow Actuator Performance: For Diesel Engine
Model” of troubleshooting for 2.DEF: Measured pressure
too low.).

• There are no leaks on the low and high pressure air

circuits referring to “Test 3: Checking the turbocharged air
inlet circuit: For Diesel Engine Model”.

• The oil vapour rebreathing system is connected.
• The fuel flow actuator (blocked/seized, perform output

test “IMV/Flow actuator” on SUZUKI scan tool.).

• The engine timing (and the position of the high pressure

pump sprocket).

Is there in good condition?

Go to Step 5.

Carry out the required
repairs.

Are the compressions correct?

End of fault finding.

Carry out the required
repairs.

Engine General Information and Diagnosis: For Diesel Engine Model 1A-364

Table 7: Irregular Engine Operation

S6JB0A1124160

Troubleshooting

Step

Action

Yes

If the engine races during gear changes, check, if there is a
floor carpet, that this is not blocking the accelerator pedal,
the brake pedal and the clutch pedal, then check the
conformity of the clutch switch and the conformity of the
accelerator pedal sensor when the pedal is released.

Is there in good condition?

Go to Step 2.

Carry out the required
repairs.

Check the following:
• CKP sensor and its circuit (refer to “DTC P0335: CKP

Sensor Circuit: For Diesel Engine Model”.).

• Check that the engine earthing is in order (oxidation,

tightness, etc.).

• Check the mounting, the air gap and the condition of the

sensor (overheating).

Is there in good condition?

Go to Step 3.

Carry out the required
repairs.

Low pressure circuit check.
Check the fuel flow actuator by applying Step 12 of the
“Table 9: Rough idle: For Diesel Engine Model” finding table.
The sealing and condition of the inlet circuit referring to “Test
3: Checking the turbocharged air inlet circuit: For Diesel
Engine Model”.
The condition of the air flow sensor referring to “Test 4: MAF
sensor: For Diesel Engine Model”.
The turbocharger referring to “Test 5: Variable geometry
turbocharger control: For Diesel Engine Model” and “Test 6:
Rotating part of a turbocharger: For Diesel Engine Model”.

Is there in good condition?

Go to Step 4.

Carry out the required
repairs.

Are the compressions correct?

End of fault finding.

Carry out the required
repairs.

1A-365 Engine General Information and Diagnosis: For Diesel Engine Model

Table 8: Fuel System Leaks

S6JB0A1124161

WARNING

When servicing fuel system, be sure to observe WARNING in “Precautions on Fuel System Service:
For Diesel Engine Model in Section 1G” to reduce the risk of fire and personal injury.

Procedure for checking for an external leak on the fuel circuit:
Clean away traces of grease with clean thinner and wipe the part or the parts concerned with cleaning cloths. Start the
engine and raise the engine coolant temperature until the diesel fuel reaches 80

°C, 176 °F. Stop the engine and check

for traces of grease on the part or parts concerned. If there are such signs, replace the part or parts concerned. Bleed
the fuel circuit and continue the checks.

Troubleshooting

Step

Action

Yes

Are there greasy marks on the priming pump? (Visual
inspection and touch check)

Check the assembly of
the elements and the
condition of the seal at
the union of the two
components, if the leak
is at the seal. Replace
the part or the parts
concerned. Bleed the
fuel circuit and continue
the checks.

Go to Step 2.

Does the diesel filter offer up traces of grease? (Visual and
tactile inspections)

Go to Step 3.

Are there greasy marks on the return pipes?

Go to Step 4.

Does the high pressure pump show traces of grease?
(Visual and tactile inspections)

Go to Step 7.

Go to Step 5.

Do the high pressure pipes and the injector rail show traces
of grease? (Visual and tactile inspections)

Go to Step 7.

Go to Step 6.

Do the injectors show traces of grease? (Visual and tactile
inspections)

Go to Step 7.

End of fault finding.

Engine General Information and Diagnosis: For Diesel Engine Model 1A-366

Table 9: Rough idle

S6JB0A1124162

Troubleshooting

Does the leak appear on the union / joint?

If the leak is on the
component, replace this
and the high pressure
pipe(s) removed at the
same time as the
component.

If the leak is on the join
of a high pressure pipe
and the component,
remove the high
pressure pipe and
perform a visual
inspection of the unions:
if you find damaged
unions, change the
defective component
and the high pressure
pipe(s) removed at the
same time as the
component.

Step

Action

Yes

Step

Action

Yes

Check the sealing and the condition of the inlet circuit
referring to “Test 3: Checking the turbocharged air inlet
circuit: For Diesel Engine Model” a nd “Test 7: Exhaust gas
recirculation valve: For Diesel Engine Model”.

Is there in good condition?

Go to Step 2.

Carry out the required
repairs.

Check the low-pressure circuit referring to “Test 2: Low
pressure circuit check: For Diesel Engine Model”.

Is there in good condition?

Go to Step 3.

Carry out the required
repairs.

Check the charging system referring to “Generator Test
(Undercharged Battery Check): For Diesel Engine Model in
Section 1J” or “Generator Test (Overcharged Battery
Check): For Diesel Engine Model in Section 1J”.

Is there in good condition?

Go to Step 4.

Carry out the required
repairs.

Check that the engine speed signal is correct using an
oscilloscope: no interference, broken tooth, etc.
If not correct, check the wiring, the position of the flywheel
and the condition of the flywheel teeth, the position and
tightness of the engine speed sensor.

Is there in good condition?

Go to Step 5.

Carry out the required
repairs.

Check the conformity of the fuel injector calibration codes
using SUZUKI scan tool.

Is it correct codes?

Go to Step 6.

Register the fuel injector
calibration code into
ECM referring to
“Registration Procedure
for the Fuel Injector
Calibration Code: For
Diesel Engine Model in
Section 1C”.

Check the correction of the fuel flow referring to “Test 8:
Injector malfunction: For Diesel Engine Model”.

Is there in good condition?

Go to Step 7.

Carry out the required
repairs.

Check the connections and wiring of the injectors and ECM.