I have a 99 Lexus ES with 250,000 miles. Bought it new, and it's been a good car. Just recently the engine feels like it quits running momentarily. First noticed it on the freeway, but then it happened on a city street at 30 mph. My mechanic has put in new spark plugs, but the problem persists. Any ideas?

 

Do you mean it shuts off or you feel a loss of power?

 

I feel a loss of power. Then I feel a momentary jerk when the power returns. The first time it happened was on the freeway at 70 mph, and each incident only lasted for a split second. But it happened about 10 times in 25 miles. The last time it happened on the freeway at about 60 mph and I felt a loss of power for about 3 seconds (or more) until I depressed the accelerator slightly, then it came back to life. Other than these incidents it seems to idle and run OK. Sorry, I forgot to mention, the VSC lights are on, and I have the following codes: P0441, P1354, P0420.

 

New catalytic converter maybe?

 

P0420 OBD-II Trouble Code - This diagnostic trouble code (DTC) is a generic powertrain code.
P1354 Lexus - Variable Valve Timing System Malfunction Bank 2
P0441 Evaporative Emission Control System Incorrect Purge Flow

Well, .. that explains that pretty nicely. a VVTI solenoid is stuffed.

 

Easy DIY fix, just be careful with the bolt when you clean/replace the screen.