dfmiller
04-20-2008, 07:31 PM
Hi everyone...am at my wit's end trying to figure out my '97 318i. The code reader says: "cat efficiency below threshold bank one". I have in the last 30 days replaced the cat cov with an aftermarket one, and both oxygen sensors. What is next? Any suggestions? The code clears and comes back on after 20 miles or so...
