Fuel Pressure Regulator: Service and Repair
Throttle Body Exploded View.:
WARNING: Do not allow smoking or the use of open flames in the area where work on the fuel system is taking place. anytime the fuel system is being worked on, disconnect the negative battery cable, except for those tests where battery voltage is required.
WARNING: Whenever fuel line fittings are loosened or disconnected, wrap a shop cloth around fitting while connecting gauge, to collect fuel. Place the cloth in an approved container.
DISASSEMBLY
1. Remove the TBI air cleaner assembly air inlet and fresh air tubes.
2. Connect fuel gage bar kit SA9127E (or equivalent) to fuel pressure test port.
Fuel Pressure Test And Pressure Relief Hookup.:
3. Install bleed hose into an approved container and open valve to bleed system pressure. Once pressure is bled, remove gauge bar adapter from fuel pressure test port and recap it.
WARNING: The pressure regulator contains a large spring under heavy compression. Use care when removing the screws to prevent personal injury.
Fuel Pressure Regulator Disassembly.:
Fuel Pressure Regulator Exploded View.:
4. Note location of the pressure regulator cover alignment slot and remove the four pressure regulator attaching screws with a No. T15 TORX). Keep the pressure regulator spring compressed while maintaining pressure on the regulator cover with your fingers.
5. Remove pressure regulator cover assembly.
6. Remove pressure regulator spring.
7. Remove pressure regulator diaphragm assembly, inspect for debris and then discard.
NOTE: The pressure regulator spring, spring seat and cover are used again when a new diaphragm assembly is installed. Clean the throttle body pressure regulator bore and valve seat thoroughly with a carburetor cleaner that does not contain methyl ethyl keytone prior to installation of a new diaphragm assembly. Allow the bore area to air dry for two minutes prior to installing the new diaphragm assembly.
ASSEMBLY
Fuel Pressure Regulator Seat At Throttle Body.:
1. Inspect the pressure regulator valve seat, which is pressed into the fuel meter body cavity, for pitting, nicks, cracks, or debris. Use a mirror (if necessary) and magnifying glass to inspect for small particles in the throttle body bore and seat. If any damage is present, the whole fuel meter body must be replaced.
2. Install the pressure regulator diaphragm assembly, making sure that it is seated in the groove of the fuel meter body.
3. Install regulator spring seat and spring into cover assembly.
4. Install cover assembly over diaphragm assembly, while aligning mounting holes and mounting pins. Align the cover assembly to the position indexed before removal.
NOTE: Use care when installing the pressure regulator cover to prevent misalignment of diaphragm and causing possible fuel leaks.
5. Apply SATURN P/N 21485277 (Loctite 242 or equivalent) to the screw threads. Install the four screws, while maintaining pressure on the regulator spring cover.
^ Torque: 2.5 Nm (22 in lbs)
6. Prime fuel system.
a. Cycle ignition "ON" for 5 seconds and then "OFF" for 10 seconds.
b. Repeat step 6a twice.
c. Crank engine until it starts (maximum starter motor cranking time is 20 seconds).
d. If engine does not start, repeat steps 6a - 6c.
7. With engine "OFF", and ignition "ON", and fuel system pressurized, check for fuel leaks around the pressure regulator assembly.
8. Inspect air cleaner gasket, and replace if torn, deteriorated, or damaged. Install air cleaner assembly. Attach air inlet and fresh air tubes.