GM 24503488 Manifold, Vacuum Source

To remove the intake manifold, first relieve the fuel pressure and disconnect the negative battery cable, ensuring the Theftlock audio system's lockout feature is off if applicable. Next, remove the TBI cover and air cleaner assembly, then raise the front of the vehicle and support it securely on jackstands while draining the coolant. Label and disconnect any wires and vacuum hoses that may interfere with the manifold removal, followed by removing the throttle and TV cables along with their brackets. Proceed to take off the TBI assembly and fuel lines, and if equipped, remove the power steering pump, tying it aside in an upright position. Remove the heater hose, then pry the engine forward for additional intake manifold clearance by first removing the torque strut-to-engine bracket nut and bolt, using a pry bar to move the engine forward, and supporting the torque strut with a bolt through the slave hole into the bracket. Afterward, remove the mounting fasteners from the intake manifold, ensuring to tighten the bolts gradually in the specified order for models through 1990, while using the same tightening sequence for 1991 and later models. Finally, separate the intake manifold and gasket from the engine, scraping off any gasket material from the mating surfaces. For installation, reverse the removal steps, using a new gasket and tightening the nuts and bolts to the specified torque in the correct sequence. Add coolant, run the engine, and check for leaks and proper operation.

This procedure may be easier with the engine rotated forward. First, relieve the fuel pressure and then disconnect the negative battery cable from the battery, ensuring that the lockout feature of the Theftlock audio system is turned off before disconnecting the battery. Next, remove the upper intake manifold assembly. Raise the front of the vehicle and support it securely on jackstands, then drain the coolant. If necessary for clearance, remove the power steering pump (if equipped) and tie it aside in an upright position. Remove the heater hose and coolant line retaining nut near the bottom of the intake manifold, followed by the mounting nuts from the intake manifold. Separate the intake manifold and gasket from the engine, scraping all traces of gasket material off the intake manifold and head gasket mating surfaces while being careful not to scratch or gouge the delicate aluminum surfaces. Clean the surfaces with a rag soaked in lacquer thinner or acetone. Installation is the reverse of removal, ensuring to use a new gasket and tighten the nuts/bolts to the specified torque. Finally, add coolant, run the engine, and check for leaks and proper operation.

Remove any debris from the bolt holes using a tap and compressed air if available, then install the intake manifold gasket.

It is important to ensure that the Theftlock audio system's lockout feature is disabled before disconnecting the battery.

Install the remaining components in reverse order of removal, change the oil and filter, refill the cooling system, start the engine, and check for leaks.