Oil Rail Pressure Meter

For Isuzu 4JX1 3.0 Litre Turbo Diesel Engines

CTI’s Oil Rail Pressure Meter is a diagnostic tool designed to verify the oil pressure in the injection system of Isuzu 4JX1 3.0 Litre Turbo Diesel engines.  The Oil Rail Pressure Meter can be retro-fit to any existing vehicle using the 4JX1 motor in approximately 1 hour by someone with handyman skills.

Rough idling, long starting crank cycles or your engine not starting are all tell tale signs that your Isuzu 4JX1 engine has compromised components in the hydraulic system.  Our Oil Rail Pressure Meter can help in identifying which components are faulty or failing based on the oil pressure readings at different engine states.

Under normal driving conditions the Oil Rail Pressure Meter readings should read between 1.00 and 3.50.  Should the meter readings fall outside of these parameters (for normal driving and no noticeable change in performance) it is possible that the oil rail sensor is faulty.

With a cold engine and the cam angle sensor disconnected, cranking the engine should give a reading above 1.20 (depending on oil temperature, battery condition, type and grade of oil used).  Note that the engine will not start with the cam angle sensor disconnected.

Under normal operation, if the Oil Rail Pressure Meter reading does not reach 1.00 the engine will not start.

Likely causes are:

• HEUI pump control voltage missing (reading should be approximately 10.00 or more)
• Loose connection (oil leak) on an injector or associated hydraulics
• Low oil in sump, and/or
• Air leak in the pickup for the hydraulic priming pump

If the Oil Rail Pressure Meter reading is above 1.00 the engine will not start.  The problem is most likely associated with other ECU inputs:

• Cam angel sensor
• Crank angle sensor
• Fuel pressure switch, and/or
• Other electronics

CTI’s Oil Rail Pressure Meter can also be used as an economy fuel gauge for Isuzu 4JX1 engines by driving with oil pressure readings below 2.5.

Oil Rail Pressure Installed in Holden Jackaroo

CTI Oil Rail Pressure Meter $98.00 inc GST

For more information on the Oil Rail Pressure Meter or if you have similar requirements for a different engine please feel free to contact us.