OEM 2004 Chevrolet Astro Intake Manifold

2004 Chevrolet Astro Parts Questions & Experts Answers

• Q: How to replace the lower intake manifold on 2004 Chevrolet Astro?

  A: The first step to replace a lower Intake Manifold is to disconnect the battery negative cable followed by engine cover removal. Start by draining the cooling system while removing the air cleaner assembly with the air cleaner outlet duct attached to the Throttle Body assembly. First disconnect the accelerator control cable that connects to the throttle shaft and bracket before cutting the cruise control cable off its attachments to the throttle shaft and bracket. The Intake Manifold requires removal of the PCV Valve Hose assembly from both its position at the Intake Manifold and the valve rocker arm cover. Also remove the nuts securing the a/c hose bracket and engine wiring harness bracket to their manifold studs. The next step requires disconnecting electrical connectors for the a/c compressor clutch and a/c high pressure cutoff switch and throttle position (TP) sensor and idle air control (IAC) motor and fuel meter body assembly connector and manifold absolute pressure (MAP) sensor and evap canister purge solenoid valve . Secure the engine wire harness to a safe location after removing the ground wire from the water outlet stud and the engine wiring harness bracket from the evap canister purge solenoid valve stud. Detach the following components from the Intake Manifold: evap canister purge valve alongside radiator inlet hose, heater hose, water pump inlet hose, and vacuum hose. Start by clearing the bolt that secures the transmission fluid filler tube to the accelerator control cable bracket then detach the accelerator control cable bracket from the Throttle Body and Intake Manifold. Start by removing the Distributor and disconnecting fuel supply and return pipes at the back of the Intake Manifold before removing the ignition control module (ICM). Access to the front Intake Manifold bolt requires drivers to remove the Drive Belt along with the a/c compressor side brace and to slightly loosen the power steering pump rear bracket nut before removing the oil filler tube bracket bolt and tube. After removing the front power steering pump bracket's bolts and nut you should leave the power steering pump and a/c compressor in place while pushing the bracket forward to reach the front Intake Manifold bolt. First clean all surfaces on the lower Intake Manifold before its removal. The Intake Manifold disassembly and assembly procedures must be followed when you decide to replace the manifold. Installation process begins with placing the lower Intake Manifold followed by repositioning the power steering pump mounting bracket for final installation of three bolts and nut as well as tightening them to 41 nm (30 ft. Lbs.). Install the a/c compressor side brace and bolts, tightening the side brace bolt to 25 nm (18 ft. Lbs.) use a torque wrench to tighten the side brace bolt to the generator bracket up to 25 nm (18 ft. Lbs.). Also tighten the side brace bolt to 25 nm (18 ft. Lbs.). Install the oil filler tube and bolt, tightening the bolt to 25 nm (18 ft. Lbs.)complete the Drive Belt installation procedure after finishing all steps. Position the engine directly at the top dead center of number one cylinder before you mount the evap canister purge valve and fuel supply and return piping at the Intake Manifold's rear position. Take out the plug for number one cylinder and turn the crankshaft to its compression position with marks (1,4) on the balancer lined up to alignment marks (2,3) on the front cover before reinserting the plug. Follow this sequence to complete the installation: first place the Distributor and icm and after that place the accelerator control cable bracket's studs and nuts onto the Intake Manifold and Throttle Body. Tighten all these elements to 12 nm (106 inch lbs.). Reconnect the vacuum hose to the Intake Manifold, install the transmission fluid fill tube and bolt to the accelerator control cable bracket, tightening the bolt to 6 nm (53 inch lbs.)the technician installed water pump inlet hose and heater hoses and radiator inlet hose. Connect all electrical connectors for the a/c compressor clutch as well as the a/c high pressure cutoff switch and throttle position (TP) sensor and idle air control (IAC) motor and fuel meter body assembly connector and manifold absolute pressure (MAP) sensor and evap canister purge solenoid valve to the engine wiring harness. Install the ground wire and nut to the water outlet stud, tightening the nut to 19 nm (14 ft. Lbs.), then install the nut and engine wiring harness bracket to the stud for the evap canister purge valve, tightening it to 8 nm (71 inch lbs.)secure the Intake Manifold stud with a torque setting of 12 nm (106 inch lbs.). If equipped, install the nut and a/c hose bracket to the Intake Manifold stud, tightening to 5 nm (44 inch lbs.)open the valve rocker arm cover and secure the PCV Valve Hose assembly to the Intake Manifold. The technician will reinstall the cruise control cable when present then mount it to the throttle shaft before anchoring it with the accelerator control cable bracket followed by installing the accelerator control cable. Complete cooling system refilling before installing the air cleaner outlet duct to the Throttle Body and air cleaner assembly then reconnect the battery negative cable while finishing with the engine cover installation.