Lexus LC Rich Running

I am sorry to hear about the issues you are experiencing with your LC. I had a similar issue with my LC a while back. The symptoms you describe—reduced power, rough running, and increased fuel consumption—sound quite familiar. Have you checked your air-fuel ratio or considered the possibility of a faulty oxygen sensor? How old are your spark plugs and air filter? These might be related to the problem you described.

Thank you for your insights! I haven't checked the air-fuel ratio myself, as I lack the necessary tools and knowledge. The oxygen sensor is something I hadn't considered, so I appreciate you bringing that up. As for the spark plugs and air filter, I replaced them about 30000 km ago, so they shouldn't be the primary cause, I think. However, how did you resolve this rich running problem in your LC? Was it indeed related to the oxygen sensor, or was it something else entirely?

In my case, it turned out to be a defective fuel injector that was the root cause of the problem. I would advise you to take your car to a trusted repair shop or a Lexus dealer as soon as possible. They will be able to diagnose the problem accurately and replace the faulty injector(s). This will prevent potential engine damage.

I wanted to express my sincere gratitude for your help and guidance! I followed your advice and took my LC to a reputable mechanic. After a thorough examination, they confirmed your suspicion: a defective fuel injector was indeed the culprit! The repair cost was 515€, but the car is now running smoothly. Your insights were invaluable in pointing me in the right direction. Thanks again!