BMW Intake Manifold DIY


BMW Intake Manifold Removal
1. Disconnect the negative cable from the battery using a wrench to loosen the terminal nut. Relieve the fuel pressure by opening the valve on the fuel rail. Open the valve on the bottom of the radiator using a wrench and drain the engine coolant to the drain pan.
2. Unplug the electrical wire from the mass air flow sensor. Label the wire with the marker and masking tape so you know its proper location. Loosen the air intake duct clamp with the screwdriver and remove the air intake housing from the engine. Remove the cover from the accelerator cable.
3. Disconnect the throttle cable from the throttle body by unhooking it. Disconnect the cruise control cable if your BMW has cruise control installed. Label each hose and electrical wire on the throttle body with the marker and masking tape. Disconnect the wires and hoses from the throttle body.
4. Pry the clamp on the brake booster hose loose with a screwdriver on the right side of the intake. Pull the old clamp and the hose off the fitting. Loosen but do not remove the upper manifold to support bracket bolts using a wrench. Loosen and remove the bolt and two nuts securing the upper manifold to the lower manifold using a wrench.
5. Label the coolant hoses using the marker and masking tape. Remove the hoses using a screwdriver to loosen the clamps. Remove the breather hose from the PCV valve. Remove the upper manifold assembly from the engine. Disconnect the dipstick tube mounting bolt using a wrench. Label the engine wiring harness connectors with a marker and masking tape.
6. Disconnect the wires by unplugging them. Remove the fuel rail with the injectors attached using a wrench. Plug the fuel lines with the fuel line plugs. Plug the fuel injector ports with the port plugs. Remove the bolts from the front and rear lower parts of the intake manifold using a wrench. Loosen the intake manifold to cylinder head bolts with a socket, ratchet and extension, but do not remove them yet.
7. Catch the nuts as you remove the bolts from the manifold using a long parts retrieval magnet in case you drop any of the small nuts. Lift the manifold away from the engine high enough to clear the studs and push the fuel lines between the intake runners. This will give you access to the remaining electrical wires. Label and disconnect the wires using a wrench.
8. Lift the manifold out of the engine compartment carefully. Cover the manifold ports on the engine with clean rags until you begin the reassembly process to prevent foreign objects from getting in the engine and causing damage.
BMW Intake Manifold Installation
9. Remove the rags covering the intake ports on the engine. Place a new gasket on the engine block between the block and the new intake manifold. Connect the wires to the starter and alternator by plugging them in or securing the nuts with a wrench. Install the front and rear lower intake manifold bolts. Tighten the bolts using a wrench.
10. Place the lower intake manifold on the block and secure the fasteners using a wrench. You may need the assistance of the parts retrieval magnet in case you drop one of the nuts. Remove the plugs from the fuel injector ports and fuel lines. Install the fuel rail on the engine and tighten the bolts with a wrench. Plug the wires into each fuel injector.
11. Reconnect the engine wiring harness according to the labels you made when you removed them. Install the oil dipstick tube and tighten the nut with a wrench. Place a new gasket between the upper and lower intake manifold parts. Install the upper intake manifold. Tighten the bolts with a wrench.
12. Attach the breather hose to the PCV valve and tighten the clamp with a screwdriver. Install the coolant hoses and tighten the clamps with a screwdriver. Install the bolt and two nuts that secure the upper intake manifold to the lower. Tighten them with a wrench. Install the upper manifold to support bolts using a wrench to tighten them.
13. Connect the brake booster hose and install a clamp. Tighten the clamp with a screwdriver. Connect the wires and hoses to the throttle body according to the labels you made when removing them. Connect the cruise control cable to the throttle body if your BMW has cruise control installed. Connect the throttle cable to the throttle body.
14. Install the accelerator cable cover. Install the air intake duct and housing to the engine. Tighten the clamp with a screwdriver. Plug the electrical wire into the mass air flow sensor. Refill the radiator and reservoir with engine coolant. Connect the negative battery cable and tighten the terminal nut with a wrench.