Lexus LX engine running lean

I also have a Lexus LX, although I don’t recall the build year, and I experienced very similar symptoms some time ago. Reduced power, rough running, and that pesky check engine light. Did you confirm if your symptoms are more noticeable when the engine is cold? I ask because I did a little digging around online, and there are several postings regarding a similar Lexus issue. How did you check the MAF sensor? Did you use an OBD2 scanner, or did you actually remove the sensor and look at it? Also, did you consider that you may have a dirty or defective injection valve?

Yes, the symptoms definitely seem more pronounced when the engine is cold. To check the MAF, I used an OBD2 scanner and the readings seemed within the normal range. I didn't physically remove the sensor to inspect it. I didn't immediately suspect the injection valves. When your LX had these symptoms, was it also the injection valves? And was the engine running lean, or some other problem? Any additional information would be great.

My apologies for not being as specific as I could have been. Yes, my symptoms were practically identical to yours, and it turned out to be faulty fuel injectors. After the replacement, the engine ran perfectly again. Given your thorough diagnostic approach with the MAF sensor, and that you are experiencing jerking, and that I had something similar happen, I would suggest taking it to a trusted mechanic to get the injection valves checked out properly. Without the right tools and expertise, diagnosing a leaky or defective injector can be tricky.

Okay, that's incredibly helpful! Thank you for sharing your experience and expertise; it definitely points me in the right direction. After taking your advice, I went to the workshop. They found that an injection valve was indeed defective and replaced all of them. The final repair cost was 515€. I appreciate your assistance.