Hi From Houston
Hello all, I am new here and I am also a fairly new BMW owner. I have a 1996 328IS. I wish I could tell you I love it but it is more of a love/hate relationship. She has given me a lot of trouble. It all started when the engine light came on the second time I filled up the tank. It would go away when the tank got below half and come back when I filled up. After a few cycles of that, it stayed on permanently. I purchased a Peake reader and determined it was a small evap leak. Well, I'll be darn if I can find it. I am on my third gas cap since I didn't like the way the new one I originally bought fit. So it is not the gas cap. I looked around and took the whole trunk apart and the passenger wheel well and still no leak to be found. I looked around the fuel filter and found rocks jammed in the filter sheild, cleaned it all up and put it back together, still no luck. Eventually, the codes changed to Oxy sensor adaption limit and oxy sensor control limit on all banks. I have new Sensors on back 4to 6 but haven't replaced the other two.
I checked for vacuum leak and can't hear or see anything even using the carb cleaner method. I just replaced the spark plugs and the coil, the ICV, the MAF, the intake temperature sensor, the secondary air pump and it's partner control valve.
I guess I forgot to give the symptom which came with the new Oxy warning. It idles rough. Over 1000 rpm, she is happy but the minute you let go of the throttle, she start sputtering and sounding pretty bad. That is the case both cold and warm. The valve for the seocndary pump is vacuum controlled and it seems to work just dandy. The same with the flap in the exhaust... I am seriously doubting a vacuum leak at this point. Someone suggested the throttle position sensor. I just don't want to keep throwing parts at the thing and I am not ready to take it to the $$$$$$$$$$$$$$$$ dealer. The shop close to me who specialize in german cars won't take cars older than 10 years...
If anyone can help me figure it out, I will be forever greatful and might throw something your way...
Thanks for listening/reading