So Fix it

Remove the valve cover. Remove the rocker arm nut from the stud by turning it counterclockwise with a wrench. Lift the rocker arm off the rocker stud.

Slide a stack of flat washers onto the rocker stud. Leave enough space at the top of the stud to fully engage the threads of the nut.

Thread the nut back onto the shaft. Tighten the nut by turning it clockwise with the wrench. As the nut threads move down the rocker stud, the rocker stud will gradually pull out of the cylinder head.

Plug the OBD I scan tool into the diagnostic port located on the drivers side dash under the steering column. The port is the same size and shape as the OBD I scan tools cable. Dont force it into the port, or you may bend the pins.

Put the key into the ignition, and turn it to the "II" position, but dont start the engine.

Turn on the scan tool. Wait for it to retrieve the codes. It will display them on the face of the scan tool.

Write down the codes.

Unplug the scan tool, and turn off the vehicle.

Open the filler cap on the fuel tank to relieve the pressure in the fuel tank. Start the engine and disconnect the fuel pump fuse in the fuse box. Allow the engine to idle until it stalls and crank the engine for at least three seconds to ensure the fuel system is empty. Replace the fuel pump fuse in the fuse box.

Remove the negative battery cable with a socket wrench to prevent the accidental discharge of fuel during the cylinder head removal. Disconnect the air cleaner assembly from the engine and detach the vacuum lines to access the cylinder head.

Detach the electrical connectors from the engine to obtain access to the cylinder head. This typically includes the electrical connectors for the fuel injector, canister purge solenoid, manifold absolute pressure sensor, throttle position sensor, oxygen sensor and engine coolant temperature sensor.

Disconnect the cables from the accelerator control bracket and remove the accelerator control bracket from the engine with a socket wrench. Raise the vehicle with a floor jack and support it on jack stands.

Remove the exhaust pipe from the exhaust manifold. Place a clean container under the drain plug for the radiator and open the drain plug. Drain the coolant into the container and store the coolant for reuse. Lower the vehicle with the floor jack.

Relieve the tension on the serpentine drive belt by turning the belt tensioner counterclockwise and detach the serpentine drive belt from its pulleys. Disconnect the alternator from the engine. Remove the bracket for the power steering pump with a socket wrench and push the pump aside to gain access to the cylinder block.

Support the engine with engine support fixture J-28467-A. Disconnect the upper motor mount with a socket wrench and remove the bracket for the drive belt tensioner.

Remove the electrical wiring from the spark plugs and disconnect the evaporative emissions line under the intake manifold. Detach the outlet coolant hose from the engine. Disconnect the transmission filler tube from the intake manifold if your vehicle has automatic transmission. Detach the fuel lines from the engine and detach the valve cover from the engine.

Record the position of the rocker arms and push rods before removing them from the cylinder block. This will allow you to install them to the correct positions later.

Note the positions of the cylinder head bolts before removing them with a socket wrench. Lift the cylinder head from the cylinder block with the intake and exhaust manifolds still attached. Remove both manifolds from the cylinder head.