SsangYong Musso. Manual — part 115
1F-44 ENGINE CONTROLS
SSANGYONG Y158
System Description
The fuel pump is an in-tank fuel pump mounted to a fuel
sender assembly. The fuel pump will remain on as long
as the engine is cranking or running and the Engine
Control Module (ECM) is receiving reference pulses from
the Crankshaft Position (CKP) sensor. If there are no
reference pulses, the ECM will turn off the fuel pump
one seconds after the engine stops running. The fuel
pump delivers fuel to the fuel rail and the fuel injectors,
where the fuel system pressure is controlled form 320
to 380 kPa (46 to 55 psi) by the fuel pressure regulator.
The excess fuel is returned to the fuel tank.
Test Description
Number(s) below refer to the step(s) number on the
diagnostic table.
2. When the engine is idling, the intake manifold vacu-
um is high. This vacuum is applied to the fuel pres-
sure regulator diaphragm, offsetting the spring
pressure inside the fuel pressure regulator and lowing
the fuel pressure.
10. If there is fuel bleeding back through the fuel return
outlet, this is due to a faulty fuel pressure regulator.
FUEL SYSTEM DIAGNOSIS
12. Fuel leaking from the fuel pump inlet is due to a
faulty one-way check valve in the fuel pump.
14. Another symptom often present when the fuel injec-
tors are leaking is hard starting. Leaking fuel injec-
tors can cause a flooding condition.
Caution: The fuel system is under pressure. To avoid
fuel spillage and the risk of personal injury or fire, it
is necessary to relieve the fuel system pressure
before disconnecting the fuel lines.
Caution: Do not pinch or restrict nylon fuel lines.
Damage to the lines could cause a fuel leak, result-
ing in possible fire or personal injury.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Remove the fuel pump fuse Ef11 form the engine
fuse box.
3. Start the engine and allow the engine to stall.
4. Crank the engine for an additional 10 seconds.
1
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 and
holding steady?
1. Disconnect the fuel pressure regulator vacuum hose.
2. Start the engine.
3. Allow the engine to idle.
4. Connect the fuel pressure regulator vacuum hose.
Did the fuel pressure decrease?
1. Allow the engine to idle
2. Disconnect the vacuum hose from the fuel pressure
regulator.
3. Connect a vacuum pump with a gauge to the fuel
pressure regulator vacuum port.
4. Apply 60 - 70 kPa (18 - 21 in. Hg) of vacuum to the
fuel pressure regulator.
Did the fuel pressure decrease?
Step
Action
Value(s)
Yes
No
Fuel System Diagnosis
320 - 380 kPa
(46 - 55 psi)
Go to Step 2
Go to Step 5
-
System OK
Go to Step 3
2
3
-
Go to Step 4
Go to Step 16
ENGINE CONTROLS 1F-45
SSANGYONG Y158
4
1. Locate and correct the cause of the vacuum restric-
tion to the fuel pressure regulator.
2. Confirm the operation of the fuel pressure regulator.
Is the repair complete?
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?
Inspect the fuel lines for a leak.
Is the problem found?
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 and
holding steady?
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?
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 and
holding steady?
With the fuel system under pressure, inspect the fuel
return outlet for leaking.
Is the problem found?
1. Repair the fuel return outlet for leaking.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified and
holding steady?
With the fuel system under pressure, inspect the fuel
inlet for leaking.
Is the problem found?
1. Repair the fuel inlet for leaking.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel pressure within the values specified and
holding steady?
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?
Step
Action
Value(s)
Yes
No
Fuel System Diagnosis (Cont’d)
320 - 380 kPa
(46 - 55 psi)
Go to Step 6
Go to Step 17
-
System OK
-
5
6
-
Go to Step 7
Go to Step 8
320 - 380 kPa
(46 - 55 psi)
System OK
-
7
8
-
Go to Step 9
Go to Step 10
320 - 380 kPa
(46 - 55 psi)
System OK
-
9
10
-
Go to Step 11
Go to Step 12
320 - 380 kPa
(46 - 55 psi)
System OK
-
11
12
-
Go to Step 13
Go to Step 14
320 - 380 kPa
(46 - 55 psi)
System OK
-
13
14
-
Go to Step 15
-
1F-46 ENGINE CONTROLS
SSANGYONG Y158
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 and
holding steady?
1. Replace the fuel pressure regulator.
2. Start the engine.
3. Allow the engine to idle.
4. Connect the fuel pressure regulator vacuum hose.
Did the fuel pressure decrease?
1. Relieve the fuel system pressure
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel system pressure below the values specified
and holding steady?
1. Relieve the fuel system pressure.
2. Install a fuel pressure gauge.
3. Turn the ignition ON.
Is the fuel system pressure below the values specified
and not holding steady?
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 and
holding steady?
Step
Action
Value(s)
Yes
No
Fuel System Diagnosis (Cont’d)
320 - 380 kPa
(46 - 55 psi)
System OK
-
16
17
-
System OK
-
320 - 380 kPa
(46 - 55 psi)
Go to Step 19
Go to Step 18
18
19
320 - 380 kPa
(46 - 55 psi)
Go to Step 6
-
320 - 380 kPa
(46 - 55 psi)
System OK
-
ENGINE CONTROLS 1F-47
SSANGYONG Y158
BLANK
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст