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Diagnostic Manual, Engines, Volume 2

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 3.1 LH Sequential Multiport Fuel Injectin System (LH-SFI)   >   32 Test


Hydraulic Test Program - Test (Fuel System Pressure and Internal Leakage Test)

Test step
DTC
Test scope
Test connection
Test condition
Nominal value
Possible cause/Remedy 1)
1.0 Fuel pressure at idle (with vacuum) Pressure gauge connected to test connection.
Engine: at Idle
Valve on pressure gauge closed.
3.2 - 3.6 bar Check fuel pumps 34 ,
Replace diaphragm pressure regulator.
2.0 Fuel pressure at idle (without vacuum) Pressure gauge connected to test connection. Engine: at Idle
Disconnect vacuum hose from diaphragm pressure regulator.
3.7 - 4.2 bar Replace diaphragm pressure regulator.
3.0 Fuel system internal leakage
Pressure gauge connected to test connection. Shut off engine.

After 30 minutes
> 3.0 bar

>2.5 bar
If pressure drops quickly, replace check valve in fuel pumps.

If pressure drops slowly, check
injectors 36 ,
Replace diaphragm pressure regulator or O-rings on diaphragm pressure regulator.