I have a 1999 BMW 540i Sport. The car lacks power on acceleration. It seems like fuel or spark is intermittent. It also stalls at low idle occasionally. Ie: backing up. It seems like a fuel sensor of some sorts is failing.

The OBC-II reads fault codes: Both faults are the simular
P1174 - Fuel Trim Adaptation Additive Bank 1 Malfunction.
P1175 - Fuel Trim Adaptation Additive Bank 2 Malfunction.
Code translation is from about.com.
I read from an M3 post (year unknown) that code states P1174 - Fuel Trim, Bank 1 Different Injection times.

I have replaced both cam sensors as BMW said it was due to a stalling problem, but that was not it or not all of it.
I have also replaced the fuel filter.

The question is…what’s wrong??? A PCV valve?