Diagnostic Information And Procedures; Fuel System Diagnosis - Suzuki AN400 Service Manual

Fuel System Diagnosis

Condition
Engine will not start or
hard to start (Gasoline
does not reach the intake
pipe)
Engine will not start or
hard to start
Engine is likely to stop
(Improper air/Fuel ratio)
Engine is likely to stop
(Fuel injector function
failure)
Engine is likely to stop
(Control circuit or sensor
function failure)
Engine is likely to stop
(Engine parts function
failure)
Engine operation failure
in high speed range
(Engine internal parts or
electrical equipment
failure)
Insufficient engine power
in high speed range
(Airflow system failure)
Insufficient engine power
in high speed range
(Control circuit or sensor
failure)
Insufficient engine power
(Engine internal parts or
electrical equipment
failure)

Diagnostic Information and Procedures

Possible cause
Clogging, bending or improper routing of
fuel filter or fuel hose.
Fuel pump failure.
Fuel pressure regulator failure.
Fuel pump injector failure.
Fuel pump relay failure.
ECM failure.
Wiring connection failure.
Throttle position sensor improperly
adjusted.
Throttle position sensor failure.
Intake air pressure sensor failure.
ECM failure.
Engine temperature sensor failure.
Intake air pressure sensor failure.
Fuel pump failure.
Fuel hose improperly routed.
Fuel pump filter clogging.
Fuel pump failure.
Fuel pressure regulator failure.
ECM failure.
Injection signal not received from ECM. Repair or replace.
Lead wire disconnection or shorted.
Battery failure or voltage too low.
ECM failure.
Fuel pressure regulator failure.
Throttle position sensor failure.
Fuel pump relay failure.
Fuel hose clogging.
ECM failure.
Insufficient fuel supply to injector due to
fuel hose blockage.
Fuel pump failure.
Throttle sensor failure.
Air leakage from throttle body joint.
Fuel pressure too low.
Throttle position sensor failure.
ECM failure.
Throttle position sensor synchronization
failure.
Fuel tank pressure control valve failure. Replace.
Injector clogged.
Throttle position sensor adjustment
failure.
Air leakage from throttle or vacuum
hose.
Fuel pump or ECM failure.
Correction / Reference Item
Clean, replace or adjust.
Replace.
Replace.
Replace.
Replace.
Replace.
Inspect or repair.
Adjust.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Clean or replace.
Replace.
Replace.
Replace.
Repair or replace.
Replace or recharge.
Replace.
Replace.
Replace.
Replace.
Clean.
Replace.
Clean and priming.
Replace.
Replace.
Repair or replace.
Repair or replace.
Replace.
Replace.
Adjust.
Clean.
Replace.
Retighten or replace.
Replace.
Fuel System: 1G-3
B705H11704001