BMW N52 Intake Manifold Removal – 1,3,5,6,7,X1,X3,X5,Z4 6 Cyl.

In order to safely remove the BMW N52 intake manifold from the engine compartment, several parts and components will need to be cleared out of the work area. Which parts and components need to be cleared out is dependent on the model vehicle being repaired and can vary in methodology.  

The following steps were performed using a 2006 530xi. There were many different models produced with the N52 engine. Some of these steps may vary depending on the model.

1. ALWAYS disconnect the negative terminal from the battery before starting this repair. Since you will be using tools around the engine compartment battery terminals, it is very easy to create a short circuit and destroy sensitive electronics. Play it safe - take a couple of minutes to disconnect the power!
2. Begin by removing the cabin filter cover by pressing the side tab and sliding the cover off.
3. Use a flat blade screwdriver and an 13mm socket to remove the cabin filter containers.
4. Next, remove the right air inlet.
5. Repeat above steps with right cabin filter container and air inlet. Note that most models will need to have the hood switch removed from the right cabin filter container.
6.  Remove the engine cover(s) from vehicle.
7. Remove the lid from the intake muffler (air filter housing) . In most models, the lid is held in place with plastic latches.
8. Using a metal pick, GENTLY lift the plastic retaining tab on the mass air flow sensor plug. Unplug the mass air flow sensor.
9. Use a flat blade screwdriver to loosen the hose clamp securing the intake pipe to the intake muffler lid.
10. Remove the lid and the mass air flow sensor from the vehicle.
11. Next, the intake pipe needs to be removed from the throttle body. Begin by loosening the hose clamp where the intake pipe is attached to the throttle body. Pull the intake pipe loose and remove any vacuum lines attached to it. We strongly recommend marking any loose connections like vacuum lines with a high visibility tape - this helps avoid missing any connections during reassembly.
12. Remove the wiring harness and its plastic mounting bracket from the strut brace. It is usually attached with two plastic rivets as shown below.
13. The strut brace is held in place with four torx bolts. These bolts strip very easily and can be expensive to replace! If you do strip one, please click here for an affordable alternative to the expensive factory replacements.
14. Use a couple of bungee cords to secure the wiring harnesses out of the work area.

Once the work area is cleared out, removing the BMW N52 intake manifold is relatively easy. The BMW Repair Guide strongly recommends replacing the crankcase vent hose and return pipe when removing the intake manifold. They are notorious for breaking while being removed. If you are planning on replacing the vent hose and return pipe, do not waste time trying to disconnect them in steps 10 and 11 below. Just break them off and continue to the next step.

1. Begin by unplugging the differential pressure sensor from the rear of the intake manifold.
2. Unplug the outer DISA valve (adjuster unit).
3. Remove the cap from the fuel rail Schrader valve. Using a small screwdriver, depress the Schrader valve to release the fuel pressure in the fuel rail. We suggest putting a rag under the valve to catch the small amount of fuel that may leak out.
4. Disconnect the fuel line from the fuel rail by releasing the plastic locking collar and pulling the line free from the rail. Remove the fuel line from the back of the intake manifold and store it safely out of the work area.
5. Using an 11mm socket, remove the three intake manifold mounting bolts that also anchor the fuel rail bracket. Use a 10mm socket to remove the two inner fuel rail bracket bolts. Remove the bracket from the vehicle.
6. Unplug the throttle body.
7. Disconnect the fuel tank vent valve.
8. Unplug the oil pressure switch.
9. Using an 11mm socket, remove the last four intake manifold fasteners.
10. The next step requires disconnecting the crankcase return pipe from the oil pan. It requires reaching down behind the intake manifold, squeezing the return pipe connection, and pulling it loose. If you are planning on replacing the return pipe, do not waste time trying to remove it....just reach down and break it off with your hand.
11. Disconnect the crankcase breather hose from the valve cover. Like the return pipe above, if you are planning on replacing the breather hose don't waste time trying to disconnect it...just break it off.
12. Grasp the intake manifold and pull it loose from the cylinder head.
13. Carefully rotate the intake manifold so the back can be accessed. Disconnect the PVC heating element.
14. Locate the wiring harness on the bottom of the intake manifold. Using a 10mm socket, remove the two wiring harness mounting bolts.
15. Unplug the inner DISA valve.
16. Unplug the fuel tank vent valve sensor.
17. Remove the fuel tank vent valve from the wiring harness bracket.
18. Disconnect the wiring harness from the back of the intake manifold.
19. Remove the intake manifold from the vehicle.

Final reassembly is very straightforward with no special procedures. We have supplied a handy checklist below with important torque values.