Suzuki Engine 2002 GRAND VITARA SQ625, Service Manual

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6-1-100 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H25 ENGINE)
DTC TROUBLESHOOTING
Step Action Yes No
1 Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Ignition System inspection :
1) Check spark plug and ignition spark of cylin-
der where misfire occurs, referring to “Spark
Plug” and “Ignition Spark Check” in Section
6F2.
Is it in good condition?
Go to Step 3. Faulty ignition coil, wire
harness or spark plug.
If OK, substitute a known-
good ECM (PCM) and
recheck.
3 Fuel Injector Circuit check :
1) Check fuel injector circuit referring to “Table
B-2” in this section.
Is it in good condition?
Go to Step 4. Repair or replace.
4 Fuel Injector Operation check :
1) Using sound scope, check each injector
operating sound at engine cranking or
idling.
Do all injectors make operating sound?
Go to Step 5. Check injector not mak-
ing operating sound.
If OK, substitute a known-
good ECM (PCM) and
recheck.
5 Fuel Pressure inspection :
1) Check fuel pressure referring to “Table B-3”
in this section.
Is check result satisfactory?
Go to Step 6. Repair or replace.
6 Fuel Injector inspection :
1) Check fuel injector(s) referring to “Fuel
Injector” in Section 6E2.
Is check result satisfactory?
Go to Step 7. Replace.
7 Ignition Timing inspection :
1) Check ignition timing referring to “Ignition
Timing Check” in Section 6F2.
Is check result satisfactory?
Go to Step 8. Adjust.
8 EGR System inspection :
1) Check EGR system referring to “EGR Sys-
tem” in Section 6E2.
Is check result satisfactory?
Go to Step 9. Repair or replace.
9 Fuel Level Sensor inspection :
1) Check fuel level sensor referring to “DTC
P0460 Diag. Flow Table” in this section.
Is check result satisfactory?
Go to Step 10. Repair or replace.
10 Engine Mechanical Systems check :
1) Check engine mechanical systems referring
to Section 6A2.
Is check result satisfactory?
Substitute a known-good
ECM (PCM) and recheck. Repair or replace.