Valve cover gasket replaced now runs rough

[Hellaphonic]

I replaced the valve cover gasket on my 2007 328 xi. I was very careful as I re installed the cover. I even made sure that after it was in place, I reached under and re-seated the gasket onto the cover before seating the studs. When torqing, I used a middle to back to front/side to side pattern...let it sit for a half hour and then did a 90 degree torqe again. I installed a Mahle gasket that says its "torqe too hard resistant"

All of the coils are tight and connectors pushed on properly. When I fired the car up, it idles very rough and the 4X4, service engine soon light and several others are on. If I bring it up to 2-3K RPM it smooths out. As soon as I bring it down to idle, it runs rough again.

FYI, I changed the gasket because it was leaking onto the exhaust and smoking really bad, however the car itself ran great...until now.

Any help would be greatly appreciated.

Thanks!

[relative4]

Possible cracked valve cover. Smoke test.

[Critter7r]

I replaced the valve cover gasket on my 2007 328 xi. I was very careful as I re installed the cover. I even made sure that after it was in place, I reached under and re-seated the gasket onto the cover before seating the studs. When torqing, I used a middle to back to front/side to side pattern...let it sit for a half hour and then did a 90 degree torqe again. I installed a Mahle gasket that says its "torqe too hard resistant"

All of the coils are tight and connectors pushed on properly. When I fired the car up, it idles very rough and the 4X4, service engine soon light and several others are on. If I bring it up to 2-3K RPM it smooths out. As soon as I bring it down to idle, it runs rough again.

FYI, I changed the gasket because it was leaking onto the exhaust and smoking really bad, however the car itself ran great...until now.

Any help would be greatly appreciated.

Thanks!

I think I see the problem ...

Valve cover torque is just 9Nm (6 1/2 lb-ft). No additional 90 degree turn. I assume that valve cover snapped like a twig when you did that 90.

[Pilgrim]

I agree with the last post. Germans are very specific with torque and with the number of turns on bolts. More is not better.

[jclausen]

Check your work

[Codes2]

Inclined to agree w/ the above posters.

I recently did mine.
I turned each by hand (socket with extension), going over a similar pattern until all were hand tight (probably an easy ten passes over every bolt).
This resulted in each seating at the same time, with no torque to the valve cover.
Then, torquing to 7.4 ft. lbs which was like an 1/8 of a turn at this point. (gasket was fully compressed and valve cover was already sitting on the head at this point, so torquing was a formality.

**EDIT** any chance you can define 'runs rough' further? Like a perfectly normal with with a skip on every revolution? (missing ignition on 1 cyl) Like, under load, how is it?