Suzuki Liana RH413, Service Manual

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1A-125 Engine General Information and Diagnosis:
Troubleshooting
Step Action Yes No
1 Check fuel pressure
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge.
3) Check fuel pressure by repeating ignition switch ON and
OFF.
Is fuel pressure then 270 – 310 kPa (2.7 – 3.1 kg/cm 2 , 38.4 –
44.0 psi)?
Go to Step 2. Go to Step 5.
2 Is 250 kPa (2.5 kg/cm 2 , 35.6 psi) or higher fuel pressure
retained for 1 minute after fuel pump is stopped at Step 1?
Go to Step 3. Go to Step 4.
3 Check fuel pressure regulator for operation
1) Start engine and warm it up to normal operating
temperature.
2) Keep it running at specified idle speed.
Is fuel pressure then within 270 – 310 kPa (2.7 – 3.1 kg/cm 2 ,
38.4 – 44.0 psi)?
Normal fuel pressure. Clogged vacuum
passage for fuel
pressure regulator or
faulty fuel pressure
regulator.
4 Is there fuel leakage from fuel feed line hose, pipe or their
joint? Fuel leakage from hose,
pipe or joint. Go to Step 10.
5 Was fuel pressure higher than spec. in Step 1? Go to Step 6. Go to Step 7.
6 1) Disconnect fuel return hose from fuel pressure regulator
and connect new return hose to it.
2) Put the other end of new return hose into approved
gasoline container.
3) Operate fuel pump.
Is specified fuel pressure obtained then?
Restricted fuel return
hose or pipe. Faulty fuel pressure
regulator.
7 Was no fuel pressure applied in Step 1? Go to Step 8. Go to Step 9.
8 With fuel pump operated and fuel return hose blocked by
pinching it, is fuel pressure applied? Faulty fuel pressure
regulator. Shortage of fuel or fuel
pump or its circuit
malfunction (refer to
“Fuel Pump and Its
Circuit Check”).
9 1) Operate fuel pump.
2) With fuel return hose blocked by pinching it, check fuel
pressure.
Is it 450 kPa (4.5 kg/cm 2 , 63.9 psi) or more?
Faulty fuel pressure
regulator. Clogged fuel filter,
restricted fuel feed hose
or pipe, faulty fuel pump
or fuel leakage from
hose connection in fuel
tank.
10 1) Disconnect fuel return hose from pressure regulator and
connect new return hose to it.
2) Insert the other end of new return hose into approved
gasoline container.
3) Check again if specified pressure is obtained.
While doing so, does fuel come out of return hose?
Faulty fuel pressure
regulator. Fuel leakage from
injector, fuel leakage
from between injector
and delivery pipe, faulty
fuel pump (faulty check
valve in fuel pump) or
fuel leakage from fuel
pressure regulator
diaphragm.