DIY: Cleaning/Replacing Idle Control Valve (ICV)-

[phillyB///M3]

Did a little maintanance today and figuered I'd make a little write up since so many people asking how to clean/ or replace their ICV.

Replacing or cleaning the “Idle Control Valve” (ICV) on an e36 M3 (OBD1 S50 Engine)

Tools Required:
-Small/Medium Flathead Screwdriver
-10mm Socket
-11mm Socket
-13mm Socket
-Flex Socket Adapter
-Socket Extensions
-Socket Ratchet
-Small Cleaning Brush
-Carb or Throttle Body Cleaner

-(NOTE:It is recommended that the intake manifold gaskets be replaced whenever the intake manifold is replaced.)
-(NOTE2: It is also recomended you replace the fuel hose clamps if removed.)

Accessing the ICV:

1-Remove intake or (air box), AFM (aka MAF, HFM), the intake elbow boot and the alternator duct.

2-Remove the 4 bolts that hold the throttle body to the manifold and set the TB aside. (10mm socket).
---(Fig. 1)--

[phillyB///M3]

** ICV should be visible with these removed. --(Fig.2 and 3)--
**At this point you could probably remove the ICV without taking off the manifold (Some members have done this).You can get more space by removing the front intake manifold support brace.

For those of you can't seem to get it out the easy way you will probably need to remove the manifold to get better visibility and space. (If you are able to remove it without taking off the manifold proceed to step #20)

[RRSperry]

And?

[phillyB///M3]

**The intake manifold is held in place with 7 nuts from above and 2 support bracket bolts from underneath. Carefully disconnect the idle air hose from the intake manifold when lifting the manifold off. (Directions in next posts)

[phillyB///M3]

Removing the Intake Manifold:

3-Next, remove oil cap and both plastic engine covers. 2 plastic tabs and 2 bolts on each cover, (10mm socket)

4-Remove the Fuel Pump fuse to disable the Fuel Pump

5-Remove the 2 bolts securing the fuel rail to the manifold (10mm socket).
--(Fig. 4)--

[phillyB///M3]

6-Disconnect the black ground wire (A)-(w/ 13mm socket), black hose (B) and the front fuel line (C). --(Fig. 5)--
** Make sure you have a rag handy- Fuel will be spilling out the fuel line but don’t worry it will eventually stop.

[phillyB///M3]

7-Starting from the front of the fuel rail slowly pull up on each fuel injector one by one till you have loosened them out the Intake Manifold holes. Pull up on the fuel rail being careful not to damage the injector tips. --(Fig. 6)--

[phillyB///M3]

8-Disconnect the rear fuel line connected to the fuel rail. If you cannot remove the rear one then just move the fuel rail as far as you can toward the passenger side and secure it. (I wrapped an old (clean) shirt around the whole fuel rail to protect the injectors)

9-Remove the brake booster line. (Give it a nice pull it should slip right off.)
--(Fig. 7)--

[phillyB///M3]

10-Remove the 2 bolts on the bottom underside of the Manifold. (10mm socket)
--(Fig. 8)--

[phillyB///M3]

11-Remove the hose located directly under the Manifold by using a small screwdriver to push back the clip. Be carefull not to break the clip.
--(Fig. 9, you could see what it looks like better with the manifold removed)--

[phillyB///M3]

12-Remove the 7 bolts on the other side of the manifold. The first 6 are a breeze but accessing the 7th one is a PIA . (blue arrows) I suggest using a flex socket adaptor for easier removal of the 7th bolt. (11mm socket)
--(Fig. 10)--

[phillyB///M3]

13-Remove the Oil Dipstick.

14-Once you’ve removed all of these pull up on the manifold and work it loose. (May require some side to side motion)

15-You could either chose to remove both connections on the bottom of the manifold (A,B) or you could just push the Manifold aside without diconnecting them like I did. (See Fig. 11)
** I would suggest placing a clean shop towels in each of the cylinder port to prevent dirt from getting in there.

[phillyB///M3]

16-Remove the clip from the electrical plug connected to the ICV. (See Fig. 13)

17-Loosen the hose clamps (If its not possible proceed to next step) (Fig. 12)

[phillyB///M3]

18-Remove ICV from rubber circle mount by pulling the metal part toward the rear of the engine bay till it slides out of the rubber part. (toward the cabin) (Fig. 13)

[phillyB///M3]

19-Once you’ve pulled it out you now have better access the hose clamps. (Fig. 14)
** If you are replacing the ICV skip the next step.

[phillyB///M3]

20-Clean the inside of the ICV with carb cleaner (or throttle body cleaner) and a small brush. (Fig. 15).

[phillyB///M3]

I used an old toothbrush, a small metal brush and some Q-tips. Once you’ve cleaned out the carbon and dirt. (Optional: Spray some silicone lubricant to lubricate flap in the ICV) Re-install ICV in its proper position.
(WARNING: be careful not to damage the inside of the valve, brush gently and do not tamper with the inside valve to much)

Install is the reverse of removal. Good luck!

(NOTE from the Bentley Manual-Poor drivability may be noticed after installing a replacement idle speed control valve. After about 10 minutes of driving, the system will adapt to the base setting of the valve and the idle speed should return to normal)

(If anyone has any suggestions on improving this thread, LMK )

Drive Hard...
Phill F.

Torque Specs: (taken from the Bentley Manual)
Lower intake manifold to cylinder head = 15nm (11 ft-lb)
Intake manifold support to manifold = 15nm (11 ft-lb)
Lower intake manifold to upper manifold = 15nm (11ft-lb)

[ADVANT123]

Excellent write up, this should be stickied. This is a good time for all you OBDII guys to install that M50 intake manifold too! Better idle and more top end power, what else could you ask for?

[///MacDaddy]

PhillyB, nice write up. Did you do this because of idle flucuation? How bad was yours and did the cleaning of the ICV totally fix it? Thanks

Also, did you replace the 6 manifold gaskets?

[NY98M3]

Whats the purpose of cleaning this out?

[beatniks325]

Whats the purpose of cleaning this out?

when it gets all gunked up your idle will bounce and drop, etc.

[Stinky]

Excellent write up, this should be stickied. This is a good time for all you OBDII guys to install that M50 intake manifold too! Better idle and more top end power, what else could you ask for?

Except us OBD-II guys don't have to remove the manifold. It's easier to access than on the S50's.

[clumpymold]

Very nice, Phill. I'll have to keep this bookmarked (and printed) for when (and if) I ever do this.

And wow, 4am?

[beatniks325]

...just a side thought, maybe you could add a link to this thread on the E36 DIY page and hopefully they host it up.

http://forums.bimmerforums.com/forum...ad.php?t=76342

[///Mr. Three]

Thanks for the writeup, well done!