BMW E36 Blog

BMW E36 M42 DISA Valve

3rd July 2008

BMW E36 M42 DISA Valve

posted in Engine, Tips & Tricks, Uncategorized |

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As you may know, I’m facing trouble with my BMW E36 318is idle and until now, I was unable to totally fix the problem. I’ve cleaned the ICV, changed oxygen sensor, checked for vacuum leaks but this didn’t solve my problem. I still have a problem in one of the knock sensors, but mechanics say that it doesn’t affect the idle in anyway. Well, although this may sound correct, but I’m going to change it anyway simply because I hate to have such a problem in my car which may cause some damage to the engine.

Now, I’ve discovered last week that my DISA valve doesn’t close. For those who don’t know what the DISA valve is, please check here and here.

BMW E36 M42 DISA Valve

I’ve tried to reach to the DISA valve and check to see if the actuator arm retracts if I turned my engine on and below 4,700 RPM. I found out that the DISA valve doesn’t close and I think this may affect the idle although I’m not 100% sure of that.

So, what I’m looking for is some help from you guys. Anyone with M42 engine can confirm that the DISA valve actuator arm retracts when you start your engine. To check that simply:

1. Reach with your hand behind the DISA diaphragm.

2. You should feel a small arm that you can press with your finger when the engine is off.

3. Now, according to the Bentely manual, the actuator arm should retract when the engine is started (at idle).

Now, can you feel the actuator arm retracts when the engine is started? Can you please confirm this?

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There are currently 2 responses to “BMW E36 M42 DISA Valve”

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  1. 1 On July 8th, 2008, DISA Valve Inspection | BMW E36 Blog said:

    […] had a chance to read my previous post BMW E36 M42 DISA Valve and check the DISA valve for me? Come on, no one with M42 engine? or are you afraid to discover a […]

  2. 2 On July 24th, 2008, BMW E36 Knock Sensors | BMW E36 Blog said:

    […] you have the same problem). Now, the knock sensor is working properly. I also asked him about the DISA valve and it turned out that I had a vacuum leak that prevented it from working […]