Page 87 of 181

PETROL INJECTION
Fault finding – Interpretation of faults17B
17B - 87V12 MR-372-J84-17B000$405.mif
SAGEM 3000
Program No.: A7
Vdiag No.: 44, 48
DF637
PRESENT
OR
STOREDLPG CYLINDER 3 COMBUSTION MISFIRE
1 DEF: Destructive misfire
2 DEF: Pollutant misfire
3 DEF: Non-compliance with emission control standards
NOTESPriority when dealing with a number of faults:
– LPG fuel system: see 17C, LPG injection,
– ignition:
DF072 Cylinder 1 ignition coil circuit
DF073 Cylinder 2 ignition coil circuit
DF074 Cylinder 3 ignition coil circuit
DF075 Cylinder 4 ignition coil circuit
– flywheel signal:
DF154 Flywheel signal sensor circuit
DF125 "Torque sensor programming"
Check whether there are other cylinders with an LPG combustion misfire fault detected
by the tool before starting the following fault finding procedure.
Conditions for applying the fault finding procedure to stored faults:
The fault appears under the following conditions:
– there must be no further electrical faults,
– the programming must have been done, particularly the flywheel target,
– warm engine (minimum 75 °C),
– run the engine at idle speed with all electrical consumers switched on for
approximately 15 minutes.
Special note:
– catalytic converter misfire: OBD warning light flashes when the fault is present then
is continuously lit,
– pollutant combustion misfire: OBD warning light lit continuously.
– engine unstable, loss of power and vibrations.
Misfiring on
cylinder 3 only
The fault is probably due to a component that can only affect this cylinder:
check the cylinder 3 pencil coil,
check the condition and conformity of the spark plugs,
check the cylinder 3 LPG injector
If everything is in order, check the same components on cylinder 2 (to cover a possible
cylinder recognition error).
The fault is probably due to a component that affects a pair of cylinders:
– check the ignition coil circuit concerned (apply interpretation of fault
DF072 Cylinder 1 ignition coil circuit
DF073 Cylinder 2 ignition coil circuit
DF074 Cylinder 3 ignition coil circuit
DF075 Cylinder 4 ignition coil circuit
– check the condition and conformity of the spark plugs.
Combustion
misfires in
cylinders 2 and 3
AFTER REPAIRFollow the instructions to confirm repair.
Deal with any other faults.
Clear the stored faults.
Page 88 of 181

PETROL INJECTION
Fault finding – Interpretation of faults17B
17B - 88V12 MR-372-J84-17B000$405.mif
SAGEM 3000
Program No.: A7
Vdiag No.: 44, 48
DF638
PRESENT
OR
STOREDLPG CYLINDER 4 COMBUSTION MISFIRE
1 DEF: Destructive misfire
2 DEF: Pollutant misfire
3 DEF: Non-compliance with emission control standards
NOTESPriority when dealing with a number of faults:
– LPG fuel system: see 17C, LPG injection,
– ignition:
DF072 Cylinder 1 ignition coil circuit
DF073 Cylinder 2 ignition coil circuit
DF074 Cylinder 3 ignition coil circuit
DF075 Cylinder 4 ignition coil circuit
– flywheel signal:
DF154 Flywheel signal sensor circuit
DF125 "Torque sensor programming"
Check whether there are other cylinders with an LPG combustion misfire fault detected
by the tool before starting the following fault finding procedure.
Conditions for applying the fault finding procedure to stored faults:
The fault appears under the following conditions:
– there must be no further electrical faults,
– the programming must have been done, particularly the flywheel target,
– warm engine (minimum 75 °C),
– run the engine at idle speed with all electrical consumers switched on for
approximately 15 minutes.
Special note:
– catalytic converter misfire: OBD warning light flashes when the fault is present then
is continuously lit,
– pollutant combustion misfire: OBD warning light lit continuously.
– engine unstable, loss of power and vibrations.
Misfiring on
cylinder 4 only
The fault is probably due to a component that can only affect this cylinder:
– check the pencil coil of cylinder 4,
– check the condition and conformity of the spark plugs,
– check the cylinder 4 LPG injector
If everything is in order, check the same components on cylinder 1 (to cover a possible
cylinder recognition error).
The fault is probably due to a component that affects a pair of cylinders:
– check the ignition coil circuit concerned (apply interpretation of fault
DF072 Cylinder 1 ignition coil circuit
DF073 Cylinder 2 ignition coil circuit
DF074 Cylinder 3 ignition coil circuit
DF075 Cylinder 4 ignition coil circuit
– check the condition and conformity of the spark plugs.
Combustion
misfires on
cylinders 1 and 4
AFTER REPAIRFollow the instructions to confirm repair.
Deal with any other faults.
Clear the stored faults.
Page 89 of 181

PETROL INJECTION
Fault finding – Interpretation of faults17B
17B - 89V12 MR-372-J84-17B000$405.mif
SAGEM 3000
Program No.: A7
Vdiag No.: 44, 48
DF639
PRESENT
OR
STOREDCOMBUSTION MISFIRE IN LPG MODE
1 DEF: Destructive misfire
2 DEF: Pollutant misfire
3 DEF: Non-compliance with emission control standards
NOTESPriority when dealing with a number of faults:
– LPG fuel system: see 17C, LPG injection,
– ignition:
DF072 Cylinder 1 ignition coil circuit
DF073 Cylinder 2 ignition coil circuit
DF074 Cylinder 3 ignition coil circuit
DF075 Cylinder 4 ignition coil circuit
– flywheel signal:
DF154 Flywheel signal sensor circuit
DF125 "Torque sensor programming"
DF059 Combustion misfire in cylinder 1,
DF060 Combustion misfire in cylinder 2,
DF061 Combustion misfire in cylinder 3,
DF062 Combustion misfire in cylinder 4.
Conditions for applying the fault finding procedure to stored faults:
The fault appears under the following conditions:
– there must be no further electrical faults,
– the programming must have been done, particularly the flywheel target,
– warm engine (minimum 75 °C),
– run the engine at idle speed with all electrical consumers switched on for approximately
15 minutes.
Special note:
– catalytic converter misfire: OBD warning light flashes when the fault is present then is
continuously lit,
– pollutant combustion misfire: OBD warning light lit continuously.
– engine unstable, loss of power and vibrations.
Check the LPG injectors.
Check the condition and conformity of the spark plugs.
Check the ignition pencil coils.
If the fault is still present, carry out the following checks:
– check the flywheel sensor,
– check the condition and cleanliness of the flywheel,
– check the flywheel sensor mounting
– check the sensor/flywheel air gap,
– check the cylinder compression's,
– check the LPG fuel system,
– check the complete ignition system (see MR 364 or 370 Mechanics, 17A, Ignition),
– check the hydraulic tappets if there is camshaft noise (see MR 364 or 370 Mechanics, 11A, Top and front of engine).
If the fault is still present, deal with the other faults, then proceed to the conformity check.
AFTER REPAIRFollow the instructions to confirm repair.
Deal with any other faults.
Clear the stored faults.