felix168

Don't know what the big fuss is, but if the code is going to be permanent until the problem is solved, bring your car back to the dealer for a new cat converter. Last I checked, your car is well within the warranty period. Plus while they're working on it, you will get a loaner.

greeknasty

i highly doubt the dealer is just going to replace the cat. thats the issue..i am 45 minutes away and with a month old baby and working 7 days a week i dont have the time to go back and forth for them to troubleshoot..i think they will test all the little things first before doing something major like a cat.
i will call tomorrow and see what they say

kitlz

greeknasty, sorry the problem returned. You can ask the dealer for valet service so you don't have to go back and forth. They'll leave you a vehicle so you're not stranded. It's perfect for someone in your situation. Good luck getting it fixed.

greeknasty

thanks for the tip i will ask. even if it costs it will be worth it

kitlz

There's no cost for valet service. The only thing is you might not be able to get an appointment right away. The dealer has to make sure they have a vehicle available to drop off. Should be minimal though.

mohrd

iTrader: (3)

since that wasn't answered earlier...yes

Dealer has to be able to diagnose it this time. Demand a loaner and leave yours there until they fix.

rxonmymind

I love electronic trails. Take a pic(safely!) of the light/code coming on and email the service manager. End of debate on their part. Your time is much to valuable for this back & forth. This will also work in your favor in the long run. Picture is worth more than "I saw it": )

greeknasty

oh yeah i did..the code doesnt go away unless i clear the light but the actual code is permananet so it stays on the ECU

Woodrow

I absolutely love Lexus service, once I'm able to convince them there really is an issue. It seems like the default response for anything that isn't blatantly obvious, is "working as designed" or "can't reproduce the symptom". No matter how nicely you're treated, multiple trips to the dealership to resolve an issue is inconvenient.

I agree with kitlz! Make them come to you with the loaner, and return your car after it has really been fixed! I would also highly recommend that you develop a good relationship with one of the service advisors, so they can understand your circumstances and preferences, and remember why it's important to take care of any future issues on the first try.

One more small thing. Today's cars are very complex, and I would say that our RXs might be among the most complex. It's unfortunate that you had this issue so early, but don't be discouraged. I honestly believe that you can look forward to a great ownership experience for as long as you choose to own the car. I once swore I would never own another Toyota product. 15 years a 4 Lexus later, I'm convinced it's one of the best built and most reliable cars we can buy.

greeknasty

i appreciate the reply..im not really discouraged but more annoyed. This is me and my wifes real first "big" purchase after months of researching so when this issue arose its more of a come the F on situation. I am glad its emissions issue vs something mechanical/engine so hopefully it will be taken care of

my question is..how sensistive is the RX's evap system? reason im asking is because the first time the light came on i had been filling up with vpower after they cleared it the first time i filled up at a BP for the first time (93octane) and the light didnt come back..but when i filled up with vpower again (and about half way thru the tank) the light came back on..i am sure it isnt an issue but i found it wierd.
i also cleaned the cap as suggested. i will expierement with BP the next 2 fillups and well see. also i do not overfill, but i do "fill up" aka let it go till it stop but dont add any more

lexus114

just curious, but i have to ask. i see your using 93 octane in it. it`s a 2014 so it doesnt require it, although may be snappier on it. (mine was on 89) try a tank or two of the 87 octane and see what happens. and also mention to them you`v been using 93 octane and see what they say. this could be as simply as the motor not burning the 93 octane correctly.

lexus114

good read here as well,

So what is causing my P0420 code?

There are a number of things that could be causing this p0420 catalyst efficiency code. The most common thing is the catalytic converter itself is no longer functioning properly. The other likely thing is the rear O2 (oxygen) sensor is no longer working properly. Other things could include exhaust leaks, damaged exhaust pipes, damaged O2 sensor wiring/connectors, plugged catalytic converter, etc.
OK, so I want to diagnose things, what do I do next?

The easiest thing to do first is a visual check of things. Visually inspect the exhaust system for leaks, check the catalytic converter for dents, holes, severe discoloration, and check for a rattle inside. If any of those syptoms are there, the converter likely needs replacement. Then, visually inspect the downstream O2 sensor (behind the converter). Check for broken wires, obvious faults, etc. If all that checks out, you'll want to check the operation of the O2 sensor. To do that, you'll need access to a scan tool or oscilliscope. Check that the waveform is pretty steady. If the reading fluctuates then the sensor is likely bad and will need to be replaced.

On some vehicles such as some Subaru models an ECM reflash will fix the problem. As you can see a P0420 can be caused by many things, so if you have any doubts as to whether you can fix the problem yourself, please seek the advice of a professional technician. Good luck!

kitlz

I only use V power in the 450h and haven't had any problems. But O2 sensors were changed on both the 300 and 330. The right side of the instrument panel lit up like a Christmas tree. It happened right after getting the 330 serviced, can't remember on the 300. Definitely annoying. At least it was a relatively simple fix and didn't reoccur.

Have you called the dealer yet?

greeknasty

alright so i ran the torque app with my bluetooth odb reader and got this info..not sure exactly what it means if it means anything but i will leave it here. if it shows issues then i will be upset as lexus couldve easily connected and seen this last time i went.

rxonmymind

Did a little digging and while not the exact same code as yours if you do see this one comes up after fixing yours its certainly related. I found this below. I wish you luck!
ML "ON" DTC P0453-Fuel in Evap system.
TSBID: 184500 Mfg Num: L-SB-0017-14 Issue Date: 2014-04-03