“Check Engine”, “AWD System” & “Advanced Ultrasonic Detecting and Ranging System” warning lights came on simultaneously during acceleration with hesitation and lack of acceleration even with accelerator pressed to the floor. This has happened on four occasions starting with about 4,700 miles on my 2019 RX-350L, then at around 5,000 and twice now at around 7,000. The second time I returned to Lexus of Albuquerque fearing problems out in the middle of no where, they determined that it was either a fuel system pressured sensor or a fuel pump malfunction but during the diagnosis process, the computer cleared itself and the malfunction went away. Over the course of two more months with little mileage put on the vehicle it has happened twice, Lexus Corporate and the dealer both recommended that it go to a dealer but not having a dealer within 200 miles it was not convenient and they further could not assure that it was safe to drive it that far. By the way, when I asked the maintenance foreman, of the dealer where it was purchased, of the problem, he said that he had heard of substandard fuel causing this series of events and recommended premium fuel. Have any of you heard of this problem before, been told this story about fuel, or offer any advise? I have not had an occurrence in over three weeks and would like to drive it home before dumping it on the dealer.

 

No one will be able to help without knowing the codes but if thats a 2019 I’d be banging on the dealerships door to get it repaired. Those other two lights probably come on any time it throws a CEL so I wouldnt worry about them.

 

Thank you and it will be returned to the dealer as soon as we are home early next week. I mainly threw that out there to see if anybody else is experiencing this anomaly. When you ask Lexus if this has happened before, you of course get the “this is the first time I have ever heard of it” reply. The fuel reply I assumed was bogus and just grasping for an answer to put off an upset customer. Thanks.

 

Go back to the dealership and tell them to not give you the death trap back until they have found the root cause of the issues. This is dangerous.

 

Maybe that answer was bogus and maybe it's not. You'll never know until they diagnose the problem.

 

I've not seen this in a newer RX, but it happened to my mom's RX in the past. I asked about all the lights coming on at the same time, and the reply was as 907rx suggested. They ALL come on. Seems dumb, to me. I have a code reader, but the code I got was ambiguous and unhelpful. I might suggest that you see if you have an independent mechanic or auto parts store that can read any codes before you drive 200 miles to the dealer, only to find out any codes you might have made, cleared during the drive.

 

The bigger issue here is the hesitation, and no acceleration when pushing the go pedal to the floor. I have the same year and model with 3800 miles, and have experienced the same thing, and more; unintended acceleration while using cruise control. I proceed to cancel cruise, and engine is still holding 4500 rpm while foot is off the throttle. I was, at that moment, ready to put transmission in neutral, but we were climbing a grade without a lot of traffic, so I watched my speed as I observed this bizarre engine behavior. The rpm finally dropped back to about 1300 rpm at 60+ mph in eighth gear. Car now sits “quarantined” in my garage until the dealer can take it. Whole episode lasted about 2-3 minutes...more than enough time to cause a deadly serious accident. This incident was reported to NHTSA today, August 30, 2019. I strongly encourage anyone that have experienced similar issues to report the incident to the NHTSA at 1-888-327-4236. They will register the incident and give you a case number and written report for your records. More importantly, they will check their database for similar incidents and possibly issue a recall.

 

Thank you very much, I wanted to know if anybody out there was having a similar experience. My Lexus acted a little differently than yours but driving home I will stay very alert for any sort of anomaly, especially accelerator related. Thanks again for your information.