GM 17113139 Manifold,Lower Intake

Disconnect the cable from the negative battery terminal. Remove the air intake duct assembly. Remove the PCV valve and hose connecting the intake manifold to the valve cover. Remove the upper intake manifold (1997 and earlier MFI models only). Tag and disconnect all electrical connectors at the throttle body and manifold. Remove the fuel lines and any wiring attached to the lower intake manifold. Remove the fuel rail bracket. Remove the spark plug wires from the coil pack. Mark the spark plug wires for reassembly. Pull them up through the intake manifold and lay them over the left side of the engine. Remove the bolt holding the heater hose tube to the right rear of the manifold. Remove the mounting nuts and separate the manifold from the cylinder head. Remove the EGR tube for cleaning. Remove the old gasket and transfer all components still attached to the old manifold to the new one. Before installing the manifold, clean the cylinder head and manifold gasket surfaces. Apply a thin coat of RTV sealant to the intake manifold and cylinder head mating surfaces. Place a new gasket on the manifold, hold the manifold in position against the cylinder head, and install the mounting nuts finger tight. Tighten the mounting nuts in several steps and in the correct sequence. Install the remaining components in the reverse order of removal.

First off, disconnect the negative battery cable. For 1994 and 1995 VIN Z models, take out the upper fan shroud, air cleaner assembly, drain the cooling system, and disconnect the radiator as well as heater hoses. Also disassemble the spark plug wires, coil and distributor by unbolting emission relays bracket and remove rear braces from drive belt tensioner, remembering to mark relationship of distributor rotor with respect to other parts before removal. Disconnect the fuel lines at TBI unit; remove accelerator cables, cruise control cables, TV cables from manifold; detach vacuum brake booster pipe; label manifold lines & wires and remove them. Move up EGR hose whilst loosening manifold mounting bolts. Prying front of manifold loose after removing all bolts for that purpose is now allowed. In case of 1996 or later models you will need to start from taking out upper fan shroud then move on to air cleaner assembly followed by draining cooling system plus disconnecting upper hoses from radiator as well as heater. Next unbolt EGR valve and take off ignition coil carefully. Remove small brace between intake manifold & AC compressor then turn engine to TDC for number one piston-prior to removing distributor. Old gasket material must be removed to guarantee clean mating surfaces during re-installation; apply RTV sealant if necessary. Be sure new gaskets are properly aligned when putting in place new intake manifold while sealant is still wet on it. Proceed accordingly tightening recommended sequence's bolts once more when finished reverse remaining steps beginning with starting engine thereafter checking for leaks.

Disconnect the cable from the negative battery terminal. Remove the air intake duct assembly. Remove the PCV valve and hose connecting the intake manifold to the valve cover. Remove the upper intake manifold (1997 and earlier MFI models only). Tag and disconnect all electrical connectors at the throttle body and manifold. Remove the fuel lines and any wiring attached to the lower intake manifold. Remove the fuel rail bracket. Remove the spark plug wires from the coil pack. Mark the spark plug wires for reassembly. Pull them up through the intake manifold and lay them over the left side of the engine. Remove the bolt holding the heater hose tube to the right rear of the manifold. Remove the mounting nuts and separate the manifold from the cylinder head. Remove the EGR tube for cleaning. Remove the old gasket and transfer all components still attached to the old manifold to the new one. Before installing the manifold, clean the cylinder head and manifold gasket surfaces. Apply a thin coat of RTV sealant to the intake manifold and cylinder head mating surfaces. Place a new gasket on the manifold, hold the manifold in position against the cylinder head, and install the mounting nuts finger tight. Tighten the mounting nuts in several steps and in the correct sequence. Install the remaining components in the reverse order of removal.

Chase the threads in the bolt holes with a tap and use compressed air to remove debris.

Apply a thin coat of RTV sealant to the mating surfaces, ensuring it does not spread into air or coolant passages during installation.

Fuel pressure regulator (CSFI) replacement involves specific steps, including O-ring replacement.

Disconnect the negative battery cable, remove the upper fan shroud, air cleaner assembly, drain the cooling system, and disconnect the upper radiator and heater hoses.

Before separating the manifold from the cylinder head, you should remove the bolt holding the heater hose tube to the right rear of the manifold.

Ensure clean mating surfaces by removing old gasket material and applying RTV sealant as needed. Install new intake manifold gaskets, making sure they align correctly, and set the manifold in place while the sealant is wet. Tighten the manifold bolts in the recommended sequence, then proceed with the remaining installation steps in reverse order, starting the engine and checking for leaks.

The final step is to install the remaining components in the reverse order of removal, ensuring everything is reassembled correctly.

Ensure clean mating surfaces by removing old gasket material and applying RTV sealant as needed. Install new intake manifold gaskets, making sure they align correctly, and set the manifold in place while the sealant is wet. Tighten the manifold bolts in the recommended sequence, then proceed with the remaining installation steps in reverse order, starting the engine and checking for leaks.