Can't solve P1093 - bank 2 too rich

[kevinkay]

Service eng light on/off for about a year. (mostly on)
Pre cat fuel trim too rich bank 2
(always only bank 2)
Seems to throw code quicker with highway driving

what I KNOW its NOT-
Definitely not the cat sensors -all new and thenreplaced and switched between banks
Not anything in the intake line - lots new and no leaks
injectors/plugs/coils switched between banks - still bank 2
Not crank case ventilation system
Idle control valve was cleaned (several times), rattles fine
Not the fuel filter/pressure regulator
not the MAF - BUT a new one kept the light off the longest
New bolts in the connection between the exhaust manifold/cat and the first muffler pipe (but I didn't replace the gasket).
I added an "O-ring" on the gas cap - its tight
compression test is good in all cylinders
Fuel tank breaker valve/purge valve replaced
new air filter
DISA "O-ring" replaced 45k miles ago - seals tight



big fear its the exhaust manifold gasket? -but no excessive noise
Changed my valve cover gasket about 60k miles ago, read it was the solution for someone else, but mine is showing no leak or smell on the outside, but could be one of the spark plug seals?

Anyone else have this code and got it corrected??
THANKS

[upallnight]

https://xoutpost.com/bmw-sav-forums/...xed-p1093.html

[kevinkay]

Thanks for the reply-
YES, I read that post before. My ICV jiggled OK, then I cleaned it and it really moved freely and clicked easy. Cleaned it 3 times over the year, felt pretty confident that it "moves" freely - is there any other criteria for it needing replacement other then its ability to move freely and "click"?
thanks

[Fifty150hs]

Originally Posted by kevinkay

Thanks for the reply-
YES, I read that post before. My ICV jiggled OK, then I cleaned it and it really moved freely and clicked easy. Cleaned it 3 times over the year, felt pretty confident that it "moves" freely - is there any other criteria for it needing replacement other then its ability to move freely and "click"?
thanks

I was getting intermittent ICV codes and problems. Pulled it and cleaned it twice and reinstalled. Like you, mine "rattled" fine. Kept getting ICV codes. Replaced the ICV last month. No problems since. Seems just becasue the ICV rattles it doesn't mean it isn't "broken".

[kevinkay]

THANKS for sharing that-
I actually ordered a new ICV after "up all nights" post, I am getting desperate to get rid of this code AND at over 200,000 miles on my X, I have to expect almost every part is starting to get tired.....

Was your car idling fine (mine is) and running fine (mine is)

[Fifty150hs]

Originally Posted by kevinkay

THANKS for sharing that-
I actually ordered a new ICV after "up all nights" post, I am getting desperate to get rid of this code AND at over 200,000 miles on my X, I have to expect almost every part is starting to get tired.....

Was your car idling fine (mine is) and running fine (mine is)

It was idling fine and running fine. I just kept getting codes like "idle control valve jammed open" which went with "too lean bank 1" and "too lean bank 2". Also got an "idle control valve stuck closed" along with "too rich bank 1" and "too rich bank 2" which makes sense. Strangely it also caused codes for transmission and transfer case. Haven't had those since replacing the ICV either. The software on these cars seems to do some strange things when a part goes bad. By the way I have 208,000+ miles on my X.

[kevinkay]

again, thanks for sharing
past year I only get the "too rich bank 2" - P1093

[Fifty150hs]

Originally Posted by kevinkay

again, thanks for sharing
past year I only get the "too rich bank 2" - P1093

Please let us know if the new ICV solves your problem.

[upallnight]

Originally Posted by kevinkay

Thanks for the reply-
YES, I read that post before. My ICV jiggled OK, then I cleaned it and it really moved freely and clicked easy. Cleaned it 3 times over the year, felt pretty confident that it "moves" freely - is there any other criteria for it needing replacement other then its ability to move freely and "click"?
thanks

The wiggle test is only one test of the ICV. Unless you can confirm that the valve is going through its entire range when it is rattling it could still be defective even though you can hear it rattling.

Did you ohmed the coil that is in the ICV? Like everything else on the BMW, the signal to the ICV is controlled by the PCM, so that mean that the signal is probably a pulse width modulated signal (PWM or pussy whipped man LOL). You would need a oscilloscope to view the duty cycle of a PWM signal.

[upallnight]

Insight on how PWM and duty cycle works.

https://www.youtube.com/watch?v=kwb4pAUxR4E