318iS Part 4: "The mess under the intake" DIY guide. And second try starting!

There's this thread that was created back in 2007 and still gets bumped up every once in a while called "The mess under the intake". It's very confusing and there's a few people in the thread that do a pretty good job explaining it, but there's no good visuals or step by step guide. So hopefully this helps some people.

This eliminates a lot of hoses which are prone to cracking and failing, it's a must do for any m42.

You will need:

Plastic Coolant Pipe from Block (Part # 11531714738) O-Ring for Pipe (The linked pipe above comes with one on it already)(Part # 11531709157) Throttle Body Gasket (Part # 13541743261) Upper – Lower Intake Gasket (Part # 11611717761) Lower Intake – Block Gasket (Part # 11611734684)

BMW Antifreeze (Part # 82141467704) 5/8” Coolant Hose (2 feet) 19/32” Vacuum Hose (3-4 feet)

Both hoses are available at any chain parts store, I got mine at autozone.

Step 1:

Drain the coolant and remove the intake manifold and lower portion, As well as the plastic pipe that is bolted to the block. Put the lower portion to the side and do not cut/remove the hose that goes to the brake booster. Use this as a good time to do some cleaning of the manifolds.

Step 2: Install the black coolant pipe.

Step 3: Hook up the two original larger hoses to the pipe

Step 3: Attach the 19/32" hose to the port in the photo. it will seem loose, you will need to really tighten the clamp down hard for a good seal. I didn't get a good photo but use about 16" of the tube and connect it to the last open port of the black plastic pipe that was installed in the last step.

Step 4: Install the lower intake manifold.

Step 5: I did not get a good photo, but completely remove the throttle body heater, this is the piece of aluminum sandwiched between the throttle body and the intake manifold. It's the metal thing in the bottom right of this photo:

Step 6: Install the ICV. This reuses the small L shaped hose that connects it to the valve cover, but the other end gets the rest of the 19/32" hose. Once that's installed, put the upper intake manifold back on.

Step 7: Hook up the small vacuum line going from the fuel rail up to the small port on the throttle body, then run the 5/8" hose from the bottom of the throttle body to the valve cover. Hook up the canister hose to the left port on the throttle body.

Step 8: Install the intake boot, cut the hose from the ICV to length, and hook it up to the port on the bottom of the boot.

Step 9: Install the air box, fill and bleed the coolant, and you are done. Here's my car starting for the first time in 10 years!