Does a 99 Malibu 3.1 inlet fuel line have a o ring if so what size

Removal Procedure
Important: Always maintain cleanliness when servicing fuel system components.
Important: There is no service interval for fuel filter replacement. Only replace a restricted fuel filter.
1. Relieve fuel system pressure. Refer to Fuel Pressure Relief . 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.


3. Disconnect the quick-connect fitting at the inlet of the fuel filter. Refer to Plastic Collar Quick Connect Fitting Service . 4. Disconnect the threaded fitting at the outlet of the fuel filter. 5. Drain any remaining fuel into an approved gasoline container. Installation Procedure
1. Remove protective caps from new filter. 2. Install a new O-ring.


3. Connect the quick-connect fitting at the inlet of the fuel filter. Refer to Plastic Collar Quick Connect Fitting Service . Notice: Refer to Fastener Notice in Cautions and Notices.
4. Connect the threaded fitting at the outlet of the fuel filter. Tighten
Use a back-up wrench in order to prevent the fuel filter from turning. Tighten the fuel filter outlet nut to 27?N·m (20?lb?ft).
5. Lower the vehicle. 6. Reconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical. 7. Inspect for fuel leaks. 7.1 Turn ON the ignition for 2?seconds. 7.2 Turn OFF the ignition for 10?seconds. 7.3 Turn ON the ignition. 7.4 Inspect for fuel leaks.

1991-94 Models - REMOVAL & INSTALLATION

1. Remove the air intake tube and resonator assembly.
   
2. Properly relieve the fuel system pressure.
   
3. Remove the bolts from the fuel line clip.
   
4. Using a 15 / 16 in. (24mm) backup wrench to prevent damage to the inlet port and bracket, disconnect the fuel inlet and return lines from the pressure regulator/fuel rail assembly.

If difficulty is encountered accessing the fuel return line nut, loosen and/or remove the fuel supply and rail attachment fasteners.

1. Disengage the fuel pressure regulator vacuum hose.

Fig. 6: Disengage the fuel pressure regulator vacuum hose

Fig. 7: Use a suitable wrench to loosen ...

1. Remove the regulator assembly attaching screw, then remove the regulator assembly. Plug the regulator port in the fuel rail with a clean rag to prevent system contamination.

Fig. 8: ... and remove the mounting screw from the pressure regulator/fuel rail assembly



Fig. 9: Remove the fuel pressure regulator assembly from the fuel rail

1. Do not remove the O-ring from the retainer in the pressure regulator fuel outlet, unless it is damaged and requires replacing. Always remove and discard the O-ring from the fuel inlet.

To install:

1. Lubricate the new fuel inlet O-ring and, if necessary, the new outlet O-ring with clean engine oil, then install the O-ring(s) in the pressure regulator assembly.
   
2. Position the regulator assembly to the fuel rail. Coat the threads of the attaching bolt with Loctite® 242 or an equivalent threadlock, then install the bolt and tighten to 106 inch lbs. (12 Nm).
   
3. Connect the fuel pressure regulator vacuum hose.
   
4. Connect the fuel inlet and return lines, then tighten the lines to 133 inch lbs. (15 Nm) using a backup wrench to prevent port damage.
   
5. Cycle the ignition switch to prime the fuel system, then start the engine and check for fuel leaks.
   
6. Turn the ignition OFF and install the air intake tube and resonator assembly.

Hope this helps (remember to rate and comment this answer).

FUEL LINES INTO FUEL RAIL HAS O RINGS AND FUEL INJECTORS HAS O RINGS.YOU HAVE TO GO TO THE DEALERSHIP TO BUY NEW O RINGS.

YEP BOTH LINES HAVE O RING YOU HAVE TO BUY O RINGS AT THE DEALERSHIP. BESURE TO TAKE O RINGS WITH YOU SO YOU CAN GET THE RIGHT SIZE.

1- remove fuel from tank, 2- take and loosen the tank straps, lower tank down far enough to disconnect the wiring and fuel lines.then lower tank to the ground. you may have to loosen the screws for the filler neck hose, inside of filler door to remove filler hose from tank. take off lock ring on fuel pump and pull pump out of tank, be carefull you may have to wiggle it out of tank as not to harm filter unless changing it. before starting on tank. disconnect battery as not to get any sparks. to install is reverse of removal.

the fuel filter is located just in front of fuel tank. relieve fuel pressure, you can do this by removing fuel pump fuse and running engine until it quits, or you can relieve pressure by shraider valve in engine compartment. squeeze the white plastic disconnect tabs together and pull the inlet line away from filter, then detach the outlet line from the filter, then unbolt the filter mounting bracket to remove fuel filter.

Make sure it is coming from pump and not fuel line.. The Fuel Pump carries a large O Ring either it's dry rot damaged or off track. Drop the fuel tank unscrew the cap fix o ring properly .

Not sure but I wanted to let you know 99 malibu has a recall for the fuel pump. It leaks.

It should use the white nylon release tools. I think there are 5-6 in the set,