my 2000 rx 300 has started to hesitate/shake/shutter at around 60mph, the motor starts to shake a little between 2000 and 3000 at this speed but when i accelerate it goes away, even the idle has been a little wierd lately. it has 120,000 miles the check engine light has been popping on and off, ran a check and code read gas cap, light shut off for a few days then on again and shutter problem persist, could really use some help, thanks everyone

 

Check DIY for IACV cleaning in the forum.

 

I just replaced the O Sensors Bank 1 and 2. Take it to a shop and see which codes come ofcourse that's not going to work if an engine lite is not on. Do not use after market part on the 3000 RX it did not work for me. My RX 1999 has 213,000 plus.

 

Go to AutoZone and get the code read.