I'm pretty new to this forum, and so glad I've found this place! I've owned BMWs all my life, and enjoy maintaining mine myself...I hope I don't put anyone off by being a girl.
My 97 328i is giving a p1421 code and I can't narrow it down to what it is.
I've done most of the work on my car myself. I keep it nice, always do the oil changes, keep up with brakes, rotors, sensors, fluids and filters. My check engine light has always come on for a day, then off randomly since I've had this car. It could be months between times when it has done this, but the light always goes off. This time however, the light has remained on. I took it to auto-zone and they said it was reading a p1421 error code, but their computer system would not bring up that code for BMWs. I've been doing my research online for this code, but other people typically have this code in conjunction with other related codes, not just a single code of p1421.
Does anyone have an idea of what it could be, or what I need to check? Minor or major?
FYI- It has just hit the 100,000 mile mark.
I've replaced the oxygen sensors around the 75k mark, could they be bad already? I thought they were supposed to last about 100k...so I'm thinking thats not the problem.
Thanks so much for any assistance you can provide.

~Ann-Marie