GM 96068642 Regulator,Fuel Pressure

To test the fuel injector, unfasten the air intake case from the throttle body and relocate it aside, then turn on the car engine and examine the pattern of the injector using a timing light; it should give a thick-cone spray. After turning off the engine ensure that the injector is not dripping, if it is dripping, replace it with one that drips not more than one droplet per minute. Remove the electrical connector from the injector and using a digital ohmmeter measure the resistance across the injector coils; if the values are out of range then replace the injector. To start the replacement begin by releasing fuel system pressure and then removing the negative terminal of the battery. Take off the fuel feed line from the throttle body, unlock the injector cap and disconnect the injector connector. Carefully blow the injector off the throttle body using air with the caution not to exceed 85 psi. The fuel filters should be cleaned if they are dirty; do so. Before fitting the new injector gently grease the O-rings with light oil and arrange them in correct position to the wiring harness. Put the injector cover back and reconnect the negative terminal of the battery and then pressurize the fuel system for leakage test fittings. The following procedure should be taken for the fuel pressure regulator; The negative terminal of the battery should be loosened, and then the pressure in the fuel system should be released, and then the fuel return hose and also the vacuum hose should be disconnected. Take out the screws and place the new regulator fitted with the O-ring that had been lubricated, place the screws back again and connect back the hoses. Connect the battery as usual and with the help of Cinus air pressurize the fuel system and look for leaks. To check the throttle opener, first release the vacuum and remove the hose, apply vacuum and it should retract the plunger if it fails replace it. For replacement, remove throttle opener and bracket, then fit the new one and adjust the throttle opener by checking rpms of the engine by using a tachometer and adjust it accordingly. ; the air valve is intended to provide additional air needed to pass the throttle plate when cold; test if it opens when the engine is cold and vice-versa for the warm engine. If it doesn't function as supposed then replace the faulty part and employ a fresh gasket when reseating the cap.

Place a metal container or shop towel under the fuel return line and cover it with a rag to catch any fuel that may spray out.