M42 MOTOR ICV (IDLE CONTROL VALVE) (ELEKTRONİK ROLANTİ KONTROL VALFİ ELCD) TEMİZLİĞİ

M42 owners;
If your idle is rough, changes rpm's, or just fails to keep the engine running, your ICV may be clogged and in need of cleaning. I was having a slightly rough idle and decided to do mine.

tools

• Flashlight would be helpful.
• 11mm socket
• Flathead screwdriver
• Throttle body (TB) cleaner
• OEM hoses if in need of replacement
• Throttle body gasket and intake manifold gasket (not technically necessary, but a good idea)

It took me about an hour to remove, clean, and put back the ICV. Plus I let the hoses dry (while out of the car) for about 20 minutes on top of that.

First, start by opening the hood with the engine off and hopefully not too hot, as you will make contact with the block and the intake manifold.

You will take off the intake tube, shown below, by loosening the screws at the blue arrows, and pulling off the hose at the red arrow. Then pull the intake tube off completely.

When I doing this, I will not take the throttle body off. On the other hand; I will;

• 1st, remove GAS & Cruise Control plastic cable retaining and the o-ring rubber.
• 2nd, remove the plastic cable-end retaining clip. Take it easy, don't break it. Pull the cables out of the housing, respectively.
• 3rd, remove the vac hose.
• 4th, remove the throttle sensor plug.

Then, just remove'em, upper intake + throttle, as a one whole piece.

Next, you remove the throttle body, by four 11mm bolts. The top two are shown with red arrows below. The bottom two are on the bottom of the TB, in the same position as the top two.

Move the throttle body off to the side, to gain access to the upper intake manifold, like this

Next, we'll disconnect the hose connecting the manifold to the ICV we wish to remove and clean. Behind the manifold, at the back of the engine bay, is the hose. Just twist it off, as shown by the red arrow.

Now it's time to remove the upper intake manifold. Undo all 5 of the 11mm nuts attaching it to the lower manifold. The nut locations are highlighted below with red arrows. The nut in the rear of the engine bay is hard to get to, but a small 11mm socket and 1/4" drive ratchet should get it out.

Next, carefully remove the manifold, by slowly lifting it up. I pried it off woodworker style using the backside of a hammer against the block. Be sure to remove it evenly though, lifting it up equally on all sides. Otherwise it will get stuck on the bolts on the manifold's drivers side. It is easiest to place it as shown

Now we have acces to the ICV. As shown below, it is attached with a rubber strap at the point shown with red arrows. The blue arrows indicate the electrical connection, which pulls of when you press down a wire clip. They also point to the hose connections, which you will also want to remove. Note the arrow on top of the ICV. It points TOWARDS the block. The part label with Bosch and the BMW part number written on it also face the front of the car. This is important. You want to put it back facing the correct direction.

Now, take the ICV and clean it. The image below shows the ports into which the tubes were plugged, and air flows, with a blue arrow. You'll want to hit it with an old toothbrush and a gratuitous soaking with the TB cleaner. You may choose to clean the throttle body itself while at it with some paper towels and the cleaner.

Let everything dry, and clean off the hoses if you'd like. One of mine was cracked and therefore replaced, but washing the oil and grease off of them will help them last longer. Replace any that are cracked! They will make your idle worse and allow unfiltered air into the engine = bad. Be sure to let everything dry, especially items that were cleaned with water (hoses.) Installation is the reverse of removal. Be sure to connect ALL the hoses - double check!