2018 RX 350 F-Sport rough idle and occasional stall at stop lights

ClearTheCode guidance (Lexus · Engine & drivetrain)

Summary: For 2018 RX 350 F-Sport rough idle and occasional stall at stop lights, work through these steps on your 2016+ vehicle:

1. Confirm the symptom — note when it happens (cold start, highway, after fuel fill, etc.).
2. Scan codes — save all pending/stored DTCs; don't clear until you've recorded them.
3. Check TSBs & recalls — look up your VIN for open campaigns and known fixes.
4. Inspect the obvious — related fuses, connectors, fluid level, and recent repairs.
5. Test the common fix — follow model-specific service procedures; one change at a time.
6. Escalate if needed — burning smell, no brakes, overheating, or stalling in traffic → shop visit.

Owner reported: My 2018 Lexus RX 350 F-Sport, with about 75k miles, has recently started acting up. When I'm at a stop light or in heavy traffic, the engine idles really rough, almost like it's going to stall. Sometimes it actually does stall, which is pretty scary.

I haven't noticed any check engine light yet, but the vibration is definitely noticeable through the steering wheel and seat. It seems to happen mor…

This is educational guidance, not a substitute for hands-on diagnosis.