BMW 740 IL Troble Codes & Repair

1998 BMW 740
100,000 MILES • V8 • 2WD • AUTOMATIC
Avatar
MR.M
  • MEMBER
  • 1 POST
PO302 = Cylinder 2 Misfire Detected. ? PO430 = Catalyst System Efficiency Below Threshold (bank 2). ? PO420 = Catalyst System Efficiency Below Threshold (bank 1). ? PO133 = 02 Sensor Circuit Slow Response (bank 1 Sensor 1).? Any idear where to start to repair these trouble codes? Car not running that good at this time misfiring and chuging.
Aug 14, 2011 at 5:20 PM
Advertisement
Avatar
DOCHAGERTY
  • ✓ASE Certified Mechanic
  • 9,606 POSTS
  • ASE Certified Mechanic
Where to start is a good question. I would see if the compression is even in all cylinders first.
Aug 22, 2011 at 1:19 AM
Avatar
DR LOOT
  • ✓ASE Certified Mechanic
  • 2,311 POSTS
  • ASE Certified Mechanic
those particular code all lead to a vacuum leak
Dec 20, 2011 at 4:33 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.