Suzuki Wagon R Manual page 3006

Troubleshooting
Step
1 Was "Engine and Emission Control System
Check" performed?
2 Is there DTC(s) other than "P0171" and "P0172"? Go to applicable DTC
3 Check intake system and exhaust system for
leakage.
Are intake system and exhaust system in good
condition?
4 Check fuel pressure referring to "Table B-3 Fuel
Pressure Check" in this section.
Is check result satisfactory?
5 Check fuel injectors referring to "Fuel Injector
Inspection" in Section 6E2.
Is check result satisfactory?
6 Visual inspection.
Check MAF sensor and air intake system for:
1) Objects which block measuring duct and
resistor of MAF sensor.
2) Other air flow which does not pass the MAF
sensor.
Are there in good condition?
7 MAF sensor performance check.
1) With ignition switch turned OFF, install scan
tool.
2) Start engine and warm up to normal opera-
tion temperature.
3) Check MAF value using scan tool, under the
following conditions.
MAF value specification
Idling: 1.0 – 4.0 g/sec.
Racing at 2500 r/min: 4.0 – 12.0 g/sec.
Is each value as specified?
8 Check ECT sensor referring to Step 3 and 4 of
DTC P0118 diag. flow table.
Is check result satisfactory?
9 Check HO2S–1 referring to Step 2 of DTC P0131
diag. flow table.
Is check result satisfactory?
ENGINE GENERAL INFORMATION AND DIAGNOSIS (M13 ENGINE) 6-2-107
Action Yes
Go to Step 2.
flow table.
Go to Step 4.
Go to Step 5.
Go to Step 6.
Go to Step 7.
Go to Step 8.
Go to Step 9.
Substitute a known-good
ECM and recheck.
No
Go to "Engine and Emis-
sion Control System
Check" in this section.
Go to Step 3.
Repair or replace.
Repair or replace.
Faulty injector(s) or its
circuit.
Repair or replace.
Go to "DTC P0102 Mass
Air Flow Circuit Low
Input" and "DTC P0103
Mass Air Flow Circuit
High Input" in this sec-
tion.
Faulty ECT sensor or its
circuit.
Faulty HO2S–1 or its cir-
cuit.