I'm sure this is nothing new to most of us on here, but I hope to solve this once and be done with it. My LC 100 has been throwing this same code over the past two years now, on and off and sometimes it would stay off for months or weeks, it varies. I've added various fuel treatments and it helped at times but it will eventually come back on. Also I have Magnaflow OEM equivalent Cat's installed as well as OEM Denso O2 sensors replaced. CEL still came back on after few months. No loss of power or anything weird with the car, just the damn light and the other two skid control lights that accompany the CEL, each time the mechanic resets it but eventually it will come back on. I live in a state where there's no emission test required and I'm considering removing the CATs, but I also read a few disadvantages of their removal. Is there an alternative to have the sensor bypass this particular code while keeping the CEL working to warn me of other issues in the future? Advice please!
Check engine just won't go away! P0430 code (1 Viewer)
- Thread starter landarcht
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
I'm not sure if you can easily bypass that one. There is a test sequence available in techstream that can help give you a clue what is actually triggering the problem.
Did you replace the upstream and downstream O2 sensors on that side? I think P0430 is the passenger side.
Did you replace the upstream and downstream O2 sensors on that side? I think P0430 is the passenger side.
Since you don't have emissions testing, you could try the old spark plug non fouler trick, spacing out the passenger rear O2.
Last edited:
This ^
Whereas a spark plug spacer my stop the CEL (P0430), it will not get a root cause. You've something going on pre CAT, likely just on bank 2, but can be upstream of just bank 2, like fuel delivery.
Posting your year and mileage would be a good idea.
Posting your year and mileage would be a good idea.
Last edited:
Fuel Delivery or upstream exhaust leak that is either excessive or near the o2/cat.
Can you get a cheap obd2 reader, and look at the o2 sensor behavior?
Fuel injector cleaning is probably a good idea regardless if you've got 150k+ miles.
If get the injectors cleaned. Mine at 217 we're pretty bad. One injector was barely spraying out two of the nozzles. That sort of thing could cause an emssions code and a generally weak motor. It's also cheaper than chasing cats and sensors and such.
I had the 430 code and replaced a cat from EasternCatalytics in PA and issue solved. Most often, the code is due to a failure in the CAT and not the sensor. Get a new CAT instead of trying alternative methods. The adapter is about $40 and a new cat is $200 shipped with front and rear gaskets, flnage bolts and sensor gasket.
