Usually you can leave the throttle body itself attached to the intake plenum (the upper part of the intake manifold). Very rare cases you will have to remove the throttle body itself though it may vary of course where space is limited. Most cases you can set the plenum to the side of the engine compartment with some harnesses intact and/or remove all connections completely and remove the plenum from the car. Don't forget to disconnect the battery.
Messy job, On the driver side you need to remove air intake assy and throttle assy to be able to remove the valve cover. On the passenger side, you have to remove the air intake plenum to get to the valve cover. Time consuming... but not impossible.
The EGR valve is located at the right rear corner of the intake manifold near the firewall you will have to remove the throttle body cover to access it
It is screwed into the intake manifold between the throttle body and the valve cover
In between the valve cover and intake manifold. Towards the front of the motor. You see your upper radiator hose goes right to it. You'll have to remove the hoses that go from your valve cover to the throttle body to access it.
The PCV valve is located in the top driver side of the engine, right by the intake manifold. The PCV valve is located in the rear valve cover, just behind the throttle body. There's a rubber hose connected to it. To remove it, just pull it out of the valve cover.
you do not need to remove intake manifold to change valve cover gaskets. intake bolts to the block. valve covers bolt to the heads EDIT: Theirs some clearance issues but you can maneuver the valve cover out.
On top passneger side of motor. look behind the alternator inside the space down a little. was a pain to remove for me. On some models the PCV valve is located in the valve cover. A hose runs from the valve to the throttle body base plate or intake manifold. On other models, the valve plugs into the intake manifold and is connected to the valve cover by a hose.
. unbolt upper intake and remove along with throttle body egr valve hans on electronic pkug on top remove that then unbolt egr vavle from lower intake
To remove the cover box to get to the fuel injector on the 2002 Envoy, first remove the intake manifold and the valve cover. You can do this by loosening the four bolts that hold the intake manifold first.Ê
Assuming this is fuel injected system, look for where the air filter hose goes into the intake manifold entrance (goes from rubber to metal). Remove the hose from the intake entrance. The intake entrance is where the cable from the gas pedal meets the intake at a device that opens the first butterfly valve. Remove the four screws that retain the throttle control section and disconnect the wires to the throttle position sensor and the idle intake control valve. The IMRC is now exposed below the intake throttle valve section. It will come off after removing the two top screws and one at the bottom. It is likely a sealed unit and not serviceable.
On some vehicles, yes.
There is one intake valve for each cylinder. It is located in the top of the head. If you remove the valve cover, you can see the stem of the valves by peeking through the caps in the valve spring. If you want to replace a valve, it will be necessary to first remove the cylinder head.