Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 1999 Lexus RX300 owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owns a 1999 Lexus RX300. While driving approximately 30 MPH, the rpms suddenly increased and the vehicle accelerated to speeds above 85 MPH. During the incident, flames were seen coming from the exhaust. The contact sustained a neck injury, which required medical attention. A police report was not filed. The vehicle was taken to an independent mechanic who indicated that the flames created a hole in the catalytic converter and the oxygen sensor was faulty. The vehicle was not repaired. The manufacturer and local dealer (o'brien Lexus in bellevue wa) were notified. The VIN was not available. The failure mileage was 179,825.
On January 17th, 2016, I took my '99 Lexus RX300 to church, parked the car, and joined the Sunday service. An hour after parking the vehicle (during which time it was not running or in use), I was told that there was smoke coming from it and went outside. Within minutes, the front end was bursting in flames. The fire destroyed the entire front portion of the car, including the engine, transmission, tires, and dashboard. I don't know what could have been the cause; it was seemingly random.
Tl* the contact owns a 1999 Lexus RX300. The contact stated that the vehicle would not start without the diagnostic code reader. If the diagnostic code reader was removed from the vehicle, the vehicle would shut off. The check engine light was illuminated. The contact stated that the vehicle was taken to a certified mechanic who stated that several different failure codes appeared for the vehicle. The vehicle was repaired several times for several codes; however, the failure recurred. The manufacturer was made aware, but was not familiar with the failure and did not offer a repair. The approximate failure mileage was 230,000.
I have read as many of the owners of 1999 Lexus RX300 SUV , I am not surprised to know that I am now a proud owner of a brand new transmission that failed on my wife while returning from greenville to columbia sc. The transmission was indicating problems by shifting slow as many other complaints that have been filed . When these transmissions start to fail you experience slow shifting when the car has been sitting , even if you let the car warm up first before moving into any gear drive or reverse. When you try to back up in reverse the transmission will not shift into gear, then jumps into gear hard. I have been in the mechanical field for 35 years working for Bridgestone/Firestone ias a managing partner of retail locations and know this is the signs of transmission problems. This vehicle has been serviced only by Lexus only. …
I want you to know during this time of Toyota problems and coverup, that we leased new a 1999 Lexus RX300, it was maintained at meade Lexus according to plan and my wife was driving on a freeway and the engine suddenly seized and the car quit working. The car had my two infant children in it at the time and she was stuck near the exit ramp with vehicles/trucks/semis bearing down on her. She and the children were scared and nearly collided with at its sudden location to stop. The car was towed to the Lexus dealer and discovered sludge had ruined the motor. They would not repair it and towed the vehicle to our garage where it sat as I made payments on it. I took Lexus to arbitration with my maintenance receipts and lost as the arbitrator said I May have abused the vehicle after the Toyota rep showed a sample of the sludge. …
My 1999 -- Lexus RX300 has about 140K miles on it. The car is now parked so I don't kill myself or my family while driving. A couple months ago, my car just started jerking as if it was going to cut off and my check engine light came on. I work off a major highway and I was really scared. My car speed would be 50-55mph but the rpms would be as high as 6. I have never experienced anything like that before. I went to the car repair shop - I had some mis-fires and they were fixed for $150, no problem. The car repair recommended I get my front brakes done because my miles per gallon had slipped to 15 in the city. A couple weeks later, I got my front brakes done, no problems until one evening, I was driving home when my check engine light came on again...this time I was at the stop light and my car started idling/jerking like I needed to give it some gas or it was going to die. …
My check engine light came on. I had the oil changed for the second time within 30 days because I thought it was an oil problem. The light went off as I was leaving the place. A couple days later the light would come on when I made turns, blink, then go back off. A few days later, it came back on steady, and the car started to jerk while I was driving on the interstate. It would jerk, then slowly increase speed. Last Saturday, I applied brakes, and the car rolled another few feet. Had to swerve left to keep from rear ending a vehicle. Today, upon slowing down to enter my driveway, it did it again, and I nearly hit a brick column at the beginning of the driveway. It doesn't jerk frequently, but it seems to do it more often when I am on cruise control. I love my SUV and am always bragging about what a reliable car it is. I can't afford to replace it, retired and on disability.
Lexus 1999 rx 300 had oil sludge in 2000 and I was originally charged by Lexus pembroke pines then about 1 year later reimbursed as a customer convience. My Lexus now has thrown a rod at 88,000 which I feel and can get expert mechanics to verify that this is the after effect of the oil gel. The only thing that was done was a oil cleaning and gasket change. The internal parts oil pump, rods,crankshaft were not dismantled and thoroughly cleaned removing any left over remnants of oil gunk which after time would restrict oil flow to the working parts. Lexus denies all liability and I feel this falls under the class action suit and I need protection which I cannot afford. Your assistance and further help in pointing out cases in complete engine breakdown will help me get Lexus to open there eyes and hopefully help others.
Had my 60,000 mile service done on my 1999 RX300. The wife drove it when I got home and told me the car was running sluggish, didn't accelerate like it did before I brought it in. I took the car out to drive it and feel what she was telling me and noticed that when I would let off the gas and coast them give it gas there was a clunking noise. I took it to the dealer, the mechanic heard the noise and said he wasn't sure what it was. The service person said that I should just drive it normal and not try to make it clunk and it should be OK. If it kept doing it to make an appointment to bring it back. Car will be out of warranty! In 4 months.
While driving on a 2 lane mountain road the engine on my 1999 Lexus rx 300 started knocking loudly and failed. I was able to swing into a pull out and did not get hit. This failure is due to sledge build up. I am a second owner of the vehicle and did not receive notice from Toyota about replacing a defective engine . I purchased vehicle in 03 had it in for repairs in 07 the dealership failed to inform me of the lawsuit and correct the engine at that time. Now this incident in 2010. I could have lost my life if I were to have been hit on this mountain road that sits on the cliff at 5,500 feet.
NHTSA investigations
Engine seizure
Engine complaints in other RX300 years
Frequently asked questions
How common are engine problems on the 1999 Lexus RX300?
NHTSA has 28 complaints about the engine & cooling of the 1999 Lexus RX300, 13% of the model year's 221 complaints. The component named most often is engine › gasoline (7 mentions).
Is there a recall for 1999 Lexus RX300 engine problems?
No. NHTSA lists no engine & cooling recall for the 1999 Lexus RX300, though it has 2 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 1999 Lexus RX300 engine problems start?
Half of the complaints with a recorded mileage happened before about 122,000 miles, and 7% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 2 fires and 1 injury to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.