27. High Pressure Fuel System Test With Valve Covers Off Cranking

27. HIGH PRESSURE FUEL SYSTEM TEST WITH VALVE COVERS OFF CRANKING

Purpose:
The purpose of this test is to inspect for leaks under the valve covers at fuel lines, FRP sensor and fuel injector body.

High Pressure Fuel System Test With Valve Covers Off Cranking
- Carry out the High Pressure Fuel System Test With Valve Covers Off Cranking. Check the fuel lines, fuel line connections and fuel injectors for leaks, cracks and correct installation during the test.







Recommended Procedure:
- Remove the right hand and left hand valve covers.
- Use a black light under the valve covers to check for residual black light dye (luminescence) which is present in new engines.
- If there are signs of black light dye (luminescence) under the valve covers, use shop air to clean off the fuel injectors paying close attention to jam nut on tops of the fuel injectors and fuel line connections. Once cleaned, check the areas again with the black light to make sure the areas are clean as well as areas under the fuel lines, fuel injectors and fuel line connections. Add 1-2 packages (30-50 mL) of black light dye (luminescence) to the fuel filter housing.
- If there is no signs of black light dye (luminescence), add black light dye (luminescence) to the fuel filter housing.
- Crank the engine for 15 seconds.
- Carry out the High Pressure Fuel System Test on the scan tool with the valve covers removed. Check the fuel lines, fuel line connections and fuel injectors for leaks or cracks during the test using the black light. If a concern is present, repair as necessary. Pay close attention to the tops of the fuel injectors and fuel line connections. If a concern is present, it may take up to 10 minutes for any black light dye (luminescence) to become visible. 25. High Pressure Fuel System Test
- Check the turbocharger bearings. Refer to the Fuel Delivery and Air Induction, Turbocharger, Bearing Clearance Check.
- If no concern is present, carry out the Fuel Injector Return Port Leak Test - No Start to continue diagnosis. 19. Fuel Injector Return Port Leak Test - No Start

Possible Causes:
- Fuel leaks

Tools Required:
None