Introduces Removaland Installation of the Isuzu Engine 4JJ1 Euro 4 N Series Fuel Rail Pressure(FRP)Regulator

 This article mainly introduces Removaland Installation of the Isuzu Engine 4JJ1 Euro 4 N Series Fuel Rail Pressure(FRP)Regulator

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Maintenance Precautions
· Add washing agent into the steam cleaner and thoroughly wash around the valve and the supply pump.
· Remove water completely by blowing the air.
· Proceed to the work after confirming that all foreign matters are removed.
· After starting the engine, confirm that there is no fuel leak.
· After replacing the valve, use a scan tool to confirm that the trouble codes are erased and the system is in normal condition.
Removal
1. Disconnect the air intake duct and hose.
. Refer to "Supply Pump"in this Section.
2. Remove the supply pump.
· Refer to"Supply Pump"in this Section.
3. Disconnect the FRP regulator harness connector
(1).

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4. Remove the FRP regulator from the fuel supply pump.
5. Remove the O-ring (small) from the supply pump
(with adapter).

Installation
1.Install the O-ring to the supply pump.
·Clean O-ring groove before installng.

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 Install the FRP regulator and the gasket to the supply pump, and temporarily fasten it with 2 bolts.
NOTE:
· When installing, take care not to tuck the O-ring in.
· Temporarily tighten the bolts by hand until the FRP regulator touches the supply pump.
3. Tighten the bolts to the specified torque.
Tightening torque:8.9 N.m (0.9kg-m/78 lbin)
4. Connect the FRP regulator harmess connector.
5. Install the fuel feed pipe.
· Refer to "Supply Pump"in this Section.
6. Install the air intake duct and the hose.
. Refer to "Supply Pump"in this Section.
Supply pump relearning After replacing FRP regulator, supply pump relearn must be performed in the following steps.
1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Command the Fuel Supply Pump Learn Resetting with the scan tool.
4. Observe the Fuel Supply Pump Status Parameter with the scan tool. Confirm the scan tool indicates Not Learned.
5. Start the engine and let idle until engine coolant temperature reads 20℃ (68F) or higher while observing the Fuel Supply Pump Status parameter with a scan tool. The scan tool parameter changes status Not Learned>Leamed.