9C - Monitor Icp While Cranking

9c. Monitor ICP While Cranking






Purpose:
To determine if the injection control system can supply enough injection control pressure to sustain starting.

Recommended Procedure:
Install NGS Tester. Access ICP and IPR PIDs on NGS Tester, and monitor PID readings while cranking the engine.

NOTE: CMP signal is required before IPR is commanded above 14%.

If ICP does not meet the minimum specification of 3450 kPa (500 psi), the injectors will not be enabled by the PCM because of insufficient rail pressure.

If IPR goes above 14%, ICP pressure should easily go above 3450 kPa (500 psi) provided that the oil reservoir is full, the IPR valve is not stuck open, the high pressure pump is building pressure and there is not an injection control pressure leak between the high pressure pump and all of the injectors.

Possible Causes:
- Injection control pressure system leak
- Oil reservoir level low
- IPR failure
- Faulty high pressure pump
- Injector O-ring leaking

Injection Control Pressure Leak Test






Removing the ICP sensor and inspecting the level in the oil rail will determine if oil is being supplied to the rail. Removing the inspection plug in the top of the reservoir will help determine if the reservoir is full. A reservoir that drains back after the engine has not been operated for a long period of time can cause a hard start condition. If reservoir empties after filling, verify it is being supplied oil from the low pressure oiling system.

Purpose:
Isolate the cause of low injection control pressure.

Recommended Procedure:

CAUTION: The engine may start!

CAUTION: Oil is under high pressure!

Note: If the ICP Adapter Cable D94T-50-A is connected to the ICP sensor connect a digital multimeter between signal return and ICP signal wires on the adapter cable. Crank the engine and monitor the signal. The digital multimeter should read 1 to 4 volts.

Right Cylinder Head Check






Remove the high pressure hose from the right cylinder head using Quick Disconnect Tool 303-625, and cover the fitting on the cylinder head with the appropriate cap from the Fuel/Oil/Turbo Protector Cap Set T94T-9395-AH. Install the plug from the Oil High Pressure Leakage Test Adapter Set 303-S626 into the high pressure hose to block it off. Crank the engine and monitor the ICP PID. If the ICP Adapter Cable D94T-50-A is connected to the ICP sensor, connect a digital multimeter between signal return and ICP signal wires on the adapter cable. Crank the engine and monitor the signal. The digital multimeter should read 1 to 4 volts.

If the engine starts or if injection control pressure is now within specification, the injection control pressure leak has been isolated to the right cylinder head. Inspect the fuel to see if oil is in the fuel. If no oil is present in the fuel, remove the valve cover, crank the engine and inspect the injector body and injector bore area for leakage.

CAUTION: The engine may start!

Note: If the ICP Adapter Cable D94T-50-A is connected to the ICP sensor connect a digital multimeter between signal return and ICP signal wires on the adapter cable. Crank the engine and monitor the signal. The digital multimeter should read 1 to 4 volts.

Left Cylinder Head Check






Remove the cap and plug, then reinstall the high pressure hose to the right cylinder head. Remove the high pressure hose from the left cylinder head using Quick Disconnect Tool 303-625, and cover the fitting on the cylinder head with the appropriate cap from the Fuel/Oil/Turbo Protector Cap Set T94T-9395-AH. Install the ICP adapter from the Oil High Pressure Leakage Test Adapter Set 303-S626 into the high pressure hose. Remove the ICP sensor and install the sensor in the end of the ICP adapter. Connect the ICP/EBP Adapter Cable D94T-50-A to the ICP sensor. Connect a digital multimeter between the signal return and ICP signal wires of the adapter cable. Crank the engine and monitor the signal. The digital multimeter should read 1 to 4 volts.

CAUTION: The engine may start!

If the engine starts or if injection control pressure is now within specification, the injection control pressure leak has been isolated to the left cylinder head.

IPR and High-Pressure Pump Test

Note: If the ICP Adapter Cable D94T-50-A is connected to the ICP sensor connect a digital multimeter between signal return and ICP signal wires on the adapter cable. Crank the engine and monitor the signal. The digital multimeter should read 1 to 4 volts.






If injection control pressure is still low after ruling out both cylinder heads as the source of injection control pressure leakage, perform the following steps to isolate the cause. Leave the ICP sensor and ICP adapter connected to the left high-pressure hose. Remove the high-pressure hose from the right cylinder head and cover the fitting on the cylinder head with the appropriate cap from the Fuel/Oil/Turbo Protector Cap Set T94T-9395-AH. Install the plug from the Oil High Pressure Leakage Test Adapter Set 303-S626 into the high-pressure hose to block it off. With the high-pressure pump effectively dead headed, crank the engine and monitor the signal. If injection control pressure is not within specification, replace the Injection Pressure Regulator (IPR) with a known good IPR and retest. If a low pressure condition still exists, the problem is most likely with the high-pressure pump or the high-pressure pump drive gear.

Tools Required:
- Fuel/Oil/Turbo Protector Cap Set 303-493 (T94T-9395-AH)
- ICP/EBP Adapter Cable 418-D003 (D94T-50-A) or equivalent
- Oil High Pressure Leakage Test Adapter Set 303-S626 (D94T-6600-A) or equivalent
- 23 Multimeter 105-00050 or equivalent
- 1/4-inch drive ratchet or breaker bar to remove inspection plug
- Quick Disconnect Tool 303-625