First I want to say thank you, cause ive read advice from this site since I bought this car(without being a member). But now ive got a problem I haven't been able to find post on. I got a 99 rx300 with alot 195k miles on it. it has new plugs, coils,ocvs timing belt etc replaced. It started with a 0300 and 0302 error coming up with light blinking. Since I had no ideal what was causing it, I took it to a Toyota mech.(he run compression test and everthing he knew, he claimed) had no ideal what was wrong with the 2nd cylinder. I thought maybe it could be the injector(so I ordered one and installed it) Now the crazy part that's got me! Same kinda miss in motor but now errors 0300, 0301, 0303, and 0304. If it was the o2 sensor I thought error would run like 2,4,6 or 1,3,5 ? if anyone has any ideal what I may be over looking plz help!

 

Trust me, you need a mechanic who's more of a mechanic than this guy is! He's supposed to be a Toyota mechanic and he has no idea what's wrong with your car? Maybe he plays a mechanic on TV or something like that, ya think??? Bet he charged you just as though he was a real mechanic, didn't he?

 

Nope he didn't charge me nothing. I think he was ashamed that he had no ideal what it was (Kenny at Toy auto). But back to the problem, I unplugged the O2 sensor in the back and most the miss is gone but car lost a lot of power, and error codes 1130 ,1150, and 0304 came up.
I quess my next move will be to replace that O2 sensor and the 4th cylinder injector.
This is my wifes car and she runs it like shes racing in formula 1. Once I asked her about it , while we were flying down the interstate, and she said "The car loves it! and just feels like it wants more !" LOL
Now she is having to drive a old 92 crown Victoria till I get this sorted out, and shes not happy about it. Im kinda in the dog house till I get he lexus fixed.

 

Did he pull the freeze frame data for that error code. That will tell you more about the conditions under which the code was set. Did he check the timing?

 

IF you do replace the A/F ratio sensor (I assume that's what you're referring to as the O2 sensor) make sure you replace it with an OEM Denso sensor. I would never use aftermarket parts (especially sensors) on a Lexus. The A/F ratio sensors especially don't play well with T/L unless they're OEM. Can be purchased on Amazon for less than half of dealer price. (maybe Kenny is used to working on "toy autos" and isn't sure what to do with a real car.) I don't like to throw parts at a car, better for the car and wallet if you know your car actually needs the parts you're throwing at it. Must be a mechanic in Tn. who actually has the ability to diagnose the problem correctly.