I have an 02 M5, with 67K She was running great until a week ago. At part throttle, or when slightly letting off throttle, the car starts to buck/stumble - almost like stalling. At first it was slight, but now it is almost un-driveable I cleaned the MAF's per the M5board instructions (Used CRC Cleaner), but it didn't help. Put Techron in the tank - no change I changed the plugs this weekend - (all of the old ones looked like they were burning clean) still no difference. I checked and cleared the codes 3x with my Peake tool and here is what I get: CD - Misfire during warmup Cyl #1 CE - Misfire during warmup Cyl #2 CF - Misfire during warmup Cyl #3 D0 - Misfire during warmup Cyl #4 D1 - Misfire during warmup Cyl #5 D2 - Misfire during warmup Cyl #6 D3 - Misfire during warmup Cyl #7 D4 - Misfire during warmup Cyl #8 D5 - Misfire during warmup multiple cylinders b3 - Catalyst system efficiency Cyl 5-8 90 - Fuel control Cyl 1-4 I've checked other boards, and some suggest CPS, TPS, even the oil separator hoses, possibly a vacuum leak, fuel filter. - All these parts will need to be replaced at this mileage, so this weekend I'm starting with the throttle position sensors - when I have the plenum cover off, is there anything I should also be looking for in terms of a vacuum leak. Any help would be appreciated - I can't drive the car the way it is, and I'm really missing it! M10za
