So i looked this up via search and found a thread from 2009. The person who started it stated that from research the 325 follows the 420. Is this true? Additionally, it was stated in the comments that the CEL can go off by adding a 1.2kohm resistor in series with the black signal wire(ecu signaler) from the downstream O2 sensor. Is this also true? The thread died before the person who had the issue confirmed if it worked. Also, is doing this safe or is it just masking the issue? Anyone know of any other ways to fix the problem(s)? Thanks in advance.