GXOutlaw

My dash lit up and my OBDII throws the code p0430 bank 2. I gather from other Lexus’s on here that its a cat or O2 sensor issue. I changed out the driver manifold a year ago and did the passenger gasket a few months back. I did not replace the O2 sensor, could that be the cause or do I need a new passenger cat?

Initially when I would erase the code, it would come back on within 5 min. About 3 weeks ago I had an a/c issue, used a recharge kit and for some reason the lights and code went away for about 100 miles. The code came back about 4 days ago and when I erased it, it stayed off for 50 miles. That gasket was hell to change and I really don't want to have to do it again to replace the manifold... Also, over the winter I tend to use 87 octane but switch to 93 in the summer, could that be the cause?

MrJason

I wouldn’t use less than 89 octane and really prefer premium. The vehicle is designed for premium fuel and your mileage will generally suffer, along with your exhaust components, if you run regular 87 octane for extended periods.

But... I’ve known people who’ve ran 87 for the entire time they owned the vehicle with no issues before.


So.... maybe... couldn’t hurt to run a few tanks and see if it straights up.

Rygar470

Or if you run 87 octane, make sure it's from a top tier like Shell, or Chevron. With detergents to cleanse your injectors.

GXOutlaw

It’s strange. I went 5 miles of highway driving and it came on. I reset it and am going on 60 miles mostly around town and city traffic and its staying off. I’ve been using Costco for fuel recently. Not a huge saving on fuel but certainly the cheapest option where I’m at.

MrJason

Read this article and watch the video at the bottom. It explains top tier vs lower tier and premium vs regular.

For those to lazy.... “yes” top tier is better.. but only use premium if your vehicle calls for it. You are pissing your money away by running premium in a car that says 87 or higher.


https://www.consumerreports.org/car-...h-extra-price/