Suzuki Engine 2002 GRAND VITARA SQ420 Service Manual page 283

6-1-142 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H25 ENGINE)
Table B-3 Fuel Pressure Check
SYSTEM DIAGRAM
(A) : Gauge (C) : Attachment
(B) : Hose 1. Injector
SYSTEM DESCRIPTION
Fuel pressure regulator keeps the fuel pressure applied to injector 290 kPa higher than that in intake manifold at
all times.
INSPECTION
NOTE:
Before using following table, check to make sure that battery voltage is higher than 11 V. If battery
voltage is low, pressure becomes lower than specification even if fuel pump and line are in good con-
dition.
Step
1 Fuel Pump Operation check :
1) Remove fuel filler cap.
2) Turn ON ignition switch.
Is fuel pump operation sound heard for 3 sec.
after ignition switch ON?
2 Fuel Pressure check (engine stops) :
1) Install fuel filler cap and fuel pressure gauge
referring to "Fuel Pressure Inspection" in
Section 6E2.
2) Operate fuel pump.
Is fuel pressure 270 – 310 kPa?
3 Is 200 kPa or higher fuel pressure retained for 1
minute after fuel pump is stopped at Step 2?
4 Fuel Pressure check (idling) :
1) Start engine and warm it up to normal oper-
ating temperature.
2) Keep it running at specified idle speed.
Is fuel pressure 210 – 260 kPa?
2. Delivery pipe
3. Fuel pressure regulator
Action
4. Fuel filter
5. Fuel pump
Yes
Go to Step 2.
Go to Step 3.
Go to Step 4.
Normal fuel pressure.
No
Go to B-1 flow table.
Go to Step 6.
Go to Step 5.
Faulty vacuum passage
for fuel pressure regula-
tor or fuel pressure regu-
lator.