N62 4.4L rough idle

[burtsplash]

I finally solved my problem. I just want to post to help somebody else.

I bought a more complete diagnostic service tool. I got some random misfires and evap codes. Those are always coming back very fast after erasing the faults. I start thinking what it could be. I suspected some vacuum leaks. I finally found a damaged evap system vacuum hose connected on the air boot between the mass airflow and the throttle body. Change this hose for a new one and the engine runs now like new and no more rough idle.

It so simple after you find it... but it can take long to find and this is what happens to me.

Cost: less than 1.00$ Pretty sure a lot more if I went to the stealer. My diagnostic tool is paid by itself.

[admranger]

Originally Posted by burtsplash

I finally solved my problem. I just want to post to help somebody else.

I bought a more complete diagnostic service tool. I got some random misfires and evap codes. Those are always coming back very fast after erasing the faults. I start thinking what it could be. I suspected some vacuum leaks. I finally found a damaged evap system vacuum hose connected on the air boot between the mass airflow and the throttle body. Change this hose for a new one and the engine runs now like new and no more rough idle.

It so simple after you find it... but it can take long to find and this is what happens to me.

Cost: less than 1.00$ Pretty sure a lot more if I went to the stealer. My diagnostic tool is paid by itself.

Any chance you can post a pic or three of the offending hose location?

[burtsplash]

There's the location

[crystalworks]

Originally Posted by dpgx5

http://www.xoutpost.com/bmw-sav-foru...ictures-3.html

Post #27 shows the update.

Xoutpost.com - powered by BMW X-sav Enthusiasts! also pdf added which also follows the thread above.

There is an update from BMW for the heads that changes the CCV from internal to external addition within the hose.

Maybe you already had the update completed on the one side?
Any records from the PO?

Is this update supposed to be done to both valve covers? And I guess this is supposed to be an improvement moving the CCV's off the valve covers?

[LVP]

Just to the one cover. I did this on mine and only had to replace the one side. It wasn't cheap....

[admranger]

Originally Posted by burtsplash

There's the location

That's what I'm talking about. Great job finding that small of a leak. I'll have to check mine now and see how brittle it is.

[squidzilla]

Where did you get the hose for 1.00?

[admranger]

Originally Posted by squidzilla

Where did you get the hose for 1.00?

I'm guessing he just replaced the short bit of vacuum hose with regular auto parts store vacuum hose, sold by the foot.

[burtsplash]

Originally Posted by burtsplash

I suspected some vacuum leaks. I finally found a damaged evap system vacuum hose connected on the air boot between the mass airflow and the throttle body. Change this hose for a new one and the engine runs now like new and no more rough idle.

After looking more deeply, I'm not sure this vacuum hose is for evap system. Tried to find where this hose goes on RealOEM but I can't find it. It's in relation with engine management for sure because my engine runs a lot smoother. Could it feed a type of a second map sensor? Could not see where the vacuum line goes after the firewall.

If somebody knows let me know.