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Old 10-12-2010, 05:11 PM
Jrcanes55 Jrcanes55 is offline
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Location: Chapel Hill, NC
Join Date: Sep 2009
Posts: 62
Mein Auto: 1998 BMW M3
DIY For Removal Of Intake Manifold and PCV Valve Replacement

So I recently found out my PCV Valve, Cyclone Separator,or Crank Case Ventilator. Whatever you want to call it started putting oil in my intake manifold. I took some pics the first time I took my intake out and posted them. I soon decided to just go ahead and do a DIY because I like doing stuff like that. So I got my parts and started.

Here is where i'll start. With tools.

If you can't read the blurbs I put in the picture, from right to left, you will need, a medium sized Philips head screwdriver, a small flathead, a small 10mm socket, a small 11mm socket, a long thin 10mm socket, two extension, one short, one long, and a ratchet. You'll also want to get some plastic bags and a sharpie and make sure you keep all the screws and nuts labeled so you don't mess anything up during re-installation.

First step is to take the small flat head and pull the clamps out from the top. Be careful when you do this. If you break one you're gonna have to get a new air-box if you want to fix it. As you can see my dad broke mine because he was to impatient and tried to pry from the bottom. (This was a while ago, all the work depicted in this DIY was done by me, I didn't break anything.)

After that you need to unscrew the two nuts on the cruise control actuator (red circles) and disconnect the air intake duct on the front (red rectangle.) Finally unplug the cable from the actuator (yellow pentagon,) and move the cable to the side. It unscrews counterclockwise and pulls out. Finally lift out the air-box and put it somewhere safe.

Next is the Mass Airflow Sensor. First unplug the cable (red rectangle) in the same way you took out the plug on the Cruise Control Actuator; set that aside as well. Then simply unscrew the hose clamp and pull it out.

Next is the ASC controller and the other thing like it. Just unscrew the tops and pull off. Same for both sets. Make sure you put some pressure on the screws. They should be pretty tight and it's easy to strip the screw, also make sure you keep the screws in separate labeled bags, they are different sizes.

Next is the intake boot. This is VERY fragile, especially if it's old. Unscrew the hose clamp (red circle) and then use the mini flat head and Slowly pry it off where the red rectangle is. It's on fairly tight so be careful. Don't try to pull it out yet as there is a hose underneath that needs to be disconnected.

To disconnect the hose take the small flathead and pry it out on the end closest to the boot. Be careful so you don't tear the boot. Now take the boot out set it aside.

Next, ASC Throttle body. This is straight forward, unscrew the two bolts. Use the 10mm small or long socket, no extension. then just set the throttle body to the side. DO NOT disconnect the cable from the throttle body. The body just slides out, it has a black plastic protector that sits the back, that is connected to the actual throttle body. Don't take it off. It's safe to just leave it connected.

Last part is the actual throttle body. It is held on by a bracket, the bracket has four bolts (red circles). You will need the long thin 10mm socket to get these out. Just unscrew them and remove the bracket. The throttle body should stay held up by the two hoses that connect on the left side. You don't need to disconnect the hoses just move the throttle body out of the way. As you can probably see there is an oil deposit on the throttle body itself (purple circle.) That's what has been causing the oil burning smell in the engine compartment.

This is the back side of the throttle body. As you can see, there is a nice layer of oil on it, and the orange ring around it.

O.K. so the intake is off. Next is the Alternator cooling intake and duct. First you have to get the air scoop thing off. It's simple. unscrew the six screws on the plastic part (red circles,) and disconnect the air duct in the back (red square.) The duct disconnects by pulling towards the engine, or away from your body if you are facing the front of the car.
The plastic part comes out by pushing out, away from you're body and then pulling up. It's not hard at all.

Next is the other end of the air duct. Just unscrew the hose clamp (red circle,) and lift off.

Last bit before you start on the intake manifold is the engine covers. It's simple, use the small flathead to take the caps off the nuts and use either of the 10mm sockets to get them off (red and blue circles.) Take the fuel rail cover off first. Then, unscrew the oil cap and pull the engine cover off. Make sure you put the oil cap back on, you don't want any crap getting in there.

When you're all done it should look like this.

This is as far as I got. I'll post again later with more instructions. I'm waiting for my PCV valve to arrive.

If you don't know what or where the PCV valve is. Here is what it looks like.

So i'm not 100% sure this is correct but I believe the PCV valve sucks uncombusted gases out of the crank case, through the hose with the arrow and puts them back through the combustion chamber. I think the explanation for the oil being sucked in is that it runs through the dipstick and it is somehow sucking it up through there. Again i'm not 100% sure so correct me if i'm wrong.

Last edited by Jrcanes55; 10-12-2010 at 05:52 PM.
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