Daewoo Nubira User Manual page 555

1F – 50IENGINE CONTROLS
Step
5
1. Relieve the fuel system pressure.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified but
not holding steady?
6 Inspect the fuel lines for a leak.
Is the problem found?
7
1. Replace the fuel line(s) as needed.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified but
not holding steady?
8
1. Remove the fuel pump assembly.
2. With the fuel pump under pressure, inspect the
fuel pump coupling hoses for leaking.
Is the problem found?
9
1. Tighten or replace the fuel pump coupling
hoses as needed.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified but
not holding steady?
10 With the fuel system under pressure, inspect the fuel
return outlet for leaking.
Is the problem found?
11
1. Replace the fuel pressure regulator.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified but
not holding steady?
12 With the fuel system under pressure, inspect the fuel
inlet for leaking.
Is the problem found?
13
1. Replace the fuel pump assembly.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified but
not holding steady?
14
1. Remove the fuel rail and the fuel injectors as
an assembly.
2. With the fuel system under pressure, inspect
all of the fuel injectors for leaking.
Is the problem found?
15
1. Replace the leaking fuel injector(s).
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified but
not holding steady?
Action Value(s) Yes
284–325 kPa Go to Step 6
(41–47 psi)
Go to Step 7
284–325 kPa System OK
(41–47 psi)
Go to Step 9
284–325 kPa System OK
(41–47 psi)
Go to Step 11
284–325 kPa System OK
(41–47 psi)
Go to Step 13
284–325 kPa System OK
(41–47 psi)
Go to Step 15
284–325 kPa System OK
(41–47 psi)
No
Go to Step 17
Go to Step 8
Go to Step 10
Go to Step 12
Go to Step 14
DAEWOO V–121 BL4