How to Remove the Intake Manifold on Vehiclesby Contributing WriterUpdated June 12, 2017
The Vehicles intake manifold is made up of two parts: the upper plenum and the lower plenum. If you are removing the manifold from the Vehicles you will need to remove the upper plenum before you can remove the lower one. The procedure can vary depending on the year and engine type of the Vehicles especially with components that you may need to remove to access the manifold. Check with your mechanic.
Under The Hood:
- How to Remove the Intake Manifold on a Ford Escape
- How to Remove the Intake Manifold on an Xterra
- How to Remove the Intake Manifold From a Nissan Maxima
Raise the hood of the Ford Escape. Locate the plastic engine appearance cover on top of the engine. Detach the cover by removing the three 8mm nuts that connect it to the valve cover studs.
Locate the hose clamps and air intake tube, near the windshield on the driver's side. The hose clamps connect the intake tube to the throttle body and air filter housing. Remove the clamps by pulling the breather hose out of the intake tube. Remove the intake tube.
Twist the cable housing and remove the throttle cable from the bracket. Pull on the cruise control cable on the throttle lever stud to remove it. Locate and squeeze the cruise control cable housing tabs and remove the cable from the bracket.
Locate the upper intake manifold and remove it by twisting off the brackets.
Take out the fuel-pump fuse from the passenger-side fuse box and then start and run the engine until it stalls. Crank the engine a few times more to ensure the fuel pressure is completely relieved.
Disconnect the truck's negative battery cable.
Remove the air-intake duct, loosening its hose clamps with a screwdriver.
Label all the hoses and electrical connectors connected to the upper plenum and then disconnect them all. This includes the vacuum hoses, the power-brake booster hose, the accelerator cables and the EVAP purge-control solenoid.
Loosen and remove the plenum bolts at the plenum's right side using a wrench, starting with the bolts at the corners and alternating back and forth at each end until you reach the bolts in the center.
Remove the mounting bolts on the left side in the same manner and then remove the upper plenum with the throttle body connected to it.
Label and detach the rear PVC hose and other hoses and connectors connected to the lower plenum.
Unbolt and remove the front and rear support brackets for the lower plenum using your wrench.
Loosen the four lower plenum bolts with the wrench, starting with the outer bolts and then the inner ones.
Remove the lower plenum from the car.
Items you will need
Removing the Upper Plenum
Remove the negative battery cable from your Nissan Maxima. Wait at least 10 minutes in order to prevent the engine cooling fan from causing any potential harm while your hands are near it. Additionally, the engine must be completely cool in order to safely remove the air intake manifold.
Use a screwdriver to remove the hose clamps around the air intake duct. Gently pull the duct from the rest of the manifold.
Disconnect the accelerator cable, cruise control cable, hoses and electrical connections from the throttle body. Coolant may be lost through some of the hoses, which can be prevented by utilizing hose clamps or plugs. Be prepared with a catch pan underneath the hoses to collect any major spills.
Disconnect the spark plug wires from both the spark plugs and the retainers on the plenum. Unbolt the distributor cap. Use a pen and tape to label each wire with its location so that you can easily return each wire to its exact location once the air intake manifold has been put back in place.
Disconnect the ground strap, which is attached to the upper plenum of the air intake manifold and use a socket wrench to loosen the bolts. There are 11 bolts on the upper intake plenum.
Remove the upper plenum, which should still be attached to the throttle body. While the upper plenum of the Maxima's intake manifold is removed, it is a good idea to clean the mounting surfaces as well as the inside of the manifold with a stiff wire and brake cleaner. Use lint-free mechanics' rags to wipe away carbon buildup.
Removing the Lower Plenum
Drain the cooling system by inserting a catch pan beneath the radiator's drain bolt. Unscrew the drain bolt and hold up a 3/8 hose with a funnel on the end of it to direct the coolant to the catch pan. Open the drain fitting with a pair of pliers and remove the radiator cap.
Remove the radiator hose from the thermostat housing and disconnect the electrical connections from the coolant temperature switch and the coolant temperature sensor. Label these connections with tape and pen as described above for the upper plenum hoses and wires.
Remove the bolts to disconnect the coolant pipes at the transmission's end of the intake manifold.
Loosen the bolts on the lower manifold by turning them in 1/4-turn increments until they can be removed by hand. The manifold may need some gentle nudging to be released from the cylinder heads, but do not pry it loose -- doing so can cause damage to the sealing surfaces, leading to vacuum leaks.
Use a scraper to remove any gasket material and sealant from the outer parts of the manifold and cylinder heads. Clean the mating surfaces with lacquer thinner or acetone so that a new gasket can be applied to the lower manifold.
Items you will need
Socket wrench with socket adapters
Flat head screwdriver
Hose plugs or clamps
Gasket kit for intake manifolds