Have only had my 04 330I ZHP MT for two months and I'm already having a problem. I originally thought I was getting a random misfire but now I'm thinking maybe its getting too much fuel. The problem is worse after reaching operating temp. When cold I get an occaisional sputter when giving it more throttle. When warm its gotten much more frequent. Two days ago, and a couple of blocks from home it started running rough and stayed that way. The ses light was on so I parked it in my drive, the idle was really rough. After it cooled I started it up to try to diagnose, the ses light was off and it was running ok. I bought a code reader and obtained the following info. P0175 System too rich bank2 Freeze frame data: Fuel sys 1 CL-Fault Fuel sys 2 CL-Fault Calc Load% 0.00 Ect (F) -40 STFT B1(%) -100.00 LTFT B1(%) -100.00 STFT B2(%) -100.00 LTFT B2(%) -100.00 The yellow emisssion status light is also lit. I can't find any info on what a CL-Fault is. The engine is stock, the only things I have done since purchasing is change the oil/filter,install new Bosch Iridium Fusion plugs, and install Predator AE. I have had the airbox out twice while cleaning the engine compartment ( it was fairly clean to start with). With light throttle pressure it runs ok, increasing pressure or climing hills causes problems. Also runs better above 2000 rpm. The car only has 37K on it. Any ideas?
A quick Google suggests mass airflow sensor problem. One other site states a faulty camshaft sensor. Have you a cold air intake or K&N filter? Oil can accumulate on the MAF sensor and interfere with its ability to calculate the mass of air coming in and thus delivers the incorrect fuel amount. Get this checked out. If you continue to run rich, you risk messing up your catalytic converters. Though it is impossible to diagnose from here. Good luck.
