Last summer, my 325i failed the NJ emissions on account high hydrocarbons (HC).
The check engine light did not pull any codes back then. As the entire NJ inspection thing has become a huge and possibly $$$$$ boondogle, I just ignored it. Car ran fine in fact-30 mpg and all that.
Two days ago, the check engine light began to blink. I pulled a 1221 (O2 sensor). What a surprise. This was the circuit that gave problems during the previous inspection two years ago.
Fact is-the O2 sensor was replaced as a result of that first inspection problem.
The CE light still came on. The root cause was (supposedly) found to be a damaged
wiring harness leading up to the O2 sensor. I had the dealer "repair" that item-because the cost of an engine wiring harness was supposed to be $$700.
Now, I want to repair the car and am looking for some feedback. Questions:
1) can the car fail emissions and not show a problem via CE light 2) Now that the car has a problem in the O2 sensor circuit-could the sensor have failed ?
3) should I just bite the bullet and replace the wiring harness ?