63. Disconnect the throttle body linkage, return springs, transmission control cable and, if equipped, the cruise control.
64. Label and then disconnect all vacuum hoses.
65. Using the holding auxiliary key, unscrew the nuts of the inlet and outlet pipes of the fuel line (see illustration). Remove and replace the fuel line O-rings.
12.65. When loosening the nuts securing the fuel supply and drain lines, do not forget to use an auxiliary holding key to prevent damage (twisting) highways
66. Remove the nuts securing the TBI block (see illustration), and remove the block from the intake manifold. Remove and replace the TBI manifold gasket.
12.66. To disconnect the throttle body of the 220 model from the intake manifold, unscrew the three nuts (indicated by arrows) (the third nut is not visible here)
67. Place the TBI block on the locking stand (Kent-Moore J-9789-118, BT-3553 or their equivalent) Note: If you do not have a stand and want to place the TBI block directly on the workbench surface (work bench), be extremely careful when servicing it - the throttle can be easily damaged.
68. Remove the screws securing the fuel flow meter housing to the throttle body and remove the meter housing from the throttle body.
69. Remove the gasket between the throttle body and the fuel flow meter body and replace it.
70. Remove the TPS unit.
71. Turn the throttle body upside down on a flat surface for greater stability and remove the IAC valve.
72. Clean the throttle body in cold cleaner. Clean metal parts thoroughly and dry with compressed air. Make sure all fuel and air passages and passages are free of dirt and burrs.
Caution: Do not immerse TPS, IAC valves, pressure regulator diaphragm, injectors or other parts containing rubber in solvent or cleaning bath. If it is necessary to clean the throttle body, the time it remains in the cleaning solution should be kept to a minimum. Some models have dust boots on the throttle body that may lose their effectiveness after being in solvent.
73. Inspect the mating surfaces for damage that may compromise the sealing of the gaskets. Inspect the throttle lever and valve for dirt or damage.
74. Turn the throttle body upside down on a flat surface for stability and install the IAC valve and TPS.
75. Install a new gasket between the throttle body and the fuel flow meter housing and install the meter to the throttle body. Apply sealant to the screws that secure the fuel flow meter housing to the throttle body and tighten them securely.
76. Install the TBI unit and tighten the nuts to the torque specified in the specifications of this chapter. Use a new gasket between the TBI block and the manifold.
77. Install new O-rings on the fuel line nuts. Tighten the fuel inlet and outlet nuts by hand to avoid stripping the threads. Using a wrench to prevent the lines from twisting, tighten the nuts securely after they are properly seated in the TBI block.
78. Connect the vacuum hoses, throttle body linkage, return springs, transmission control cable, and, if equipped, cruise control. Attach the grommet with the wire harness to the throttle body.
79. Connect all electrical connectors, ensuring they are fully seated and snapped into place.
80. Check the accelerator pedal travel.
81. Connect the cable to the battery and, after stopping the engine and turning on the ignition, check for leaks on the fuel supply and drain line nuts.
82. Adjust the minimum idle speed and check the TPS output signal (see paragraphs 84-93).
83. Install the air filter, adapters and gaskets.
(The article is based on data from the website CHEVYMAN.RU)