Loss of power on m3 help please!

Hi, im from Peru and i own a 2001 manual e46 m3 with 42k miles on it.
My car was running at 80% cause i had it scanned and dealer told me i had to change the camshaft sensor (exhaust), it was running fine but lacking a lil power cause of it.

When i finally changed it ( 2 days ago ) and after deleting all the error codes and memory my m3 was lacking like 50% power ! after a scan it showed it was running lean so i changed the MAF...after changing it it was still the same. Ive checked the fuel pump and it seems OK, ive allready changed the spark plugs, filters etc.

The wierd part is that scan shows NO error codes now but it still lacks lots of power.
I had to leave my car at the dealer and he has no idea whats wrong with it....he told me that i have to use the car so that the ecu learns...and after a couple hundred miles it should b OK.......dunno how true this can be.

Any ideas on what can be wrong with it ?? any help would be apreciated ..THANKS !!

Were you able to write down the codes?

If so, post them.

it shows NO codes now...just the oil temp sensor wich i have to change.
what was showing is the additive and multiplicative % of the AFR was at +25%, i think it means the ecu was sending +25% more fuel to compensate it.....dunno at what % it should be working.

if the ecu is trying to add more fuel you could have a clogged fuel filter. how many miles do you have and when was the last time you changed the fuel filter also check for air leaks

the fuel filter was changed 1000 miles ago....allready checked for air leaks...
this is driving me crazy