Vacuum? Catalytic conv? Bad O2 sensor? '92 bmw 525i : It has been running ok but low fuel mileage and exhaust leak. muffler shop tightened exhaust manifold and fixed leak. ran for 1 day then extremely low rough idle and surging as driving and fault code for O2 sensor. I replaced leaking PCV elbow and grommet at brake booster and a cracked air intake tube. Car started and idled perfect but stalls after 5 -10 minutes and wont restart which I assume is when engine is up to or close to operating temp. before replacement of 2 previous mentioned parts, i could keep it running by constant rev or when it surged i could stomp it a couple times and it would regain power. Help please this is an elderly friend's vehicle and she has no money so she is counting on me
Oct 23, 2011 at 4:02 PM
