| Disconnect negative cable from battery. |
 |
| Loosen clamp on intake hose at airflow meter (yellow arrow).
Disconnect altitude sensor and air flow meter (blue arrows). Loosen two 10mm nuts
retaining air filter housing (green arrows) and remove the assembly. |
 |
| Loosen clamp on intake boot, remove wiring from clips on boot
and remove from air box. |
 |
| Disconnect accelerator cable and cruise cable if fitted, by
squeezing plastic tabs together and pulling retainer from bracket (blue arrow).
Remove nuts (green arrows) holding cable bracket to intake air box. Place cables, still in
bracket, aside. |
 |
| Remove vacuum hose to brake booster from intake manifold (blue
arrow), remove nut clamping hose to intake manifold (green arrow). Fold hose back out of
way. Aluminum fitting will often pull out of intake manifold. Clean fitting and
hole, apply Loctite to fitting and re-install. |
 |
| Remove hose from fitting on bottom of air box (yellow arrow).
Unscrew nut on brace below air box (green arrow). |
 |
| Remove hose from front of intake manifold beside number 1 throttle body.
Remove nuts attaching air box to throttle bodies, remove air box. |
 |
 |
| Pull off vacuum line from junction between numbers 1 and 2
throttle bodies. Remove upper hose from idle valve. Disconnect other idle valve hose from
fitting between numbers 3 and 4 throttle bodies. Remove idle valve from rubber holder. |
 |
| Lever up injector harness, disconnect idle valve extension
harness (green arrow) and pull injector harness out from between fuel pressure regulator
and cylinder head. |
 |
| Disconnect throttle position sensor. |
 |
| Remove purge hose from rear left of valve cover. (for
clearance only) |
 |
| Remove two 10mm bolts securing fuel rail to manifold (one
pictured, green arrow) and pull injectors out of manifold. Remove vacuum line
(yellow arrow) from fuel pressure regulator. Vacuum hose will more than likely need to be
cut off. Replace hose on re-assembly. |
 |
| Remove the two 10mm nuts retaining coolant bypass pipe to the
left side of the head. Remove the pipe from the hose at the front of the head and move the
pipe aside. Plug hose with a bolt to avoid coolant loss.
Intake can be removed without this step if hose clamps on elbow hose at front of head
are not interfering with the manifold. |
 |
| Remove nut retaining engine harness to number 4 throttle body,
place harness to the side. |
 |
| Remove all the E8 (external Torx) nuts securing the intake
manifold to the cylinder head. Slide intake manifold off studs. |
 |
| Remove the E8 nuts securing the gaskets to the throttle bodies
and remove gaskets. |
 |
|
|
Installation:
|
|
| Clean mating surfaces completely. |
|
| Although not called for by BMW, it has been found that
installation of the paper intake manifold gaskets from an E28 M5 will prolong the life of
the rubber M3 gaskets. Install the paper gaskets against the head, followed by the intake
manifold with rubber gaskets mounted. |
| Replace O-rings on fuel injectors. |
|
| Ensure correct positioning of idle control valve harness
bracket (green arrow) when installing fuel injector rail. Replace vacuum hose for fuel
pressure regulator. (yellow arrow) |
|
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