MR ED

I have a 02 LS430 that I bought almost 3 months ago. About a month ago the CEL came on and it came on and off as I was driving the car randomly for the first 2 weeks. The CEL is now on all the time. The car still drives fine but the first 3 - 5 mins when I start the car from a cold start it seems to run a bit dog'ish and not as smooth as it does after those 5 mins. I cleared the code this past weekend and it came back on within 10 miles of driving.

I checked the code and it's code P0430. A buddy of mine thinks it's passenger side catalytic converter. I am in a bit of a bind since my emissions is due next month and I need to get this resolved before my emissions is due.The car just hit 100K miles, is it common for catalytic converters to need to be replaced on these cars? Another buddy who used to be a mechanic at a Toyota dealership thinks that it's either a vacuum leak or a loose sensor somewhere. Any one here have any ideas?

Tom57

Is there a tiny exhaust leak before the catalytic converter? Are there any other codes with P0430? I would focus on the O2 sensors after first checking for an exhaust leak.

I'd say it's not common for a catalytic to fail at 100K (OE catalytic converters on my '01 with 265K miles), but each vehicle and how it's maintained, climate, etc. is unique.

Edit: The "Y" exhaust pipe is known to fail and leak.

Jks24

Buy and o2 sensor spacer for $5 to get rid of your cel if the converter is bad. Also tom57 is right the y pipe would cause that the heat shield attached to the car rubs against the y pipe and makes a pinhole in the pipe which could cause it to give you that cel.

MR ED

Checked for exhaust leaks and didn't find anything. Should I get an o2 spacer for both banks or just the passenger side?

P0430 is the only code that I'm getting. If the y pipe has a leak would I be able to hear the exhaust leak?

Jks24

Just grab it for both of them its like $11 for both spacers. Get them both just to be safe and the hole on your y pipe could be anything from a tiny pin hole to a massive hole. So theres no guarantee you could hear it.

Tom57

Note: The O2 spacer is used on the downstream O2 sensor (behind the catalytic converter).

P0430 is the passenger side fault code. Personally, I wouldn't install a spacer on the driver's side. "If it ain't broke, don't fix it."

Also, understand that the spacer is basically defeating / muting the purpose of the O2 sensor, by taking it out of the direct exhaust stream and thereby making it less sensitive.

Finally, the spacer may not work. If it doesn't, you may have to replace either the Y-pipe and/or the downstream O2 sensor. Dealers "smoke" the exhaust to visibly detect leaks in the exhaust pipes.

MR ED

I would like to fix the issue permanently if possible rather than a band aid fix. Might do band-aid fix just to pass emissions as long as it hopefully clears the CEL.

If I had to replace the catalytic converter. Does it bolt on or it it a one piece with the manifold?

Coulter

It's a common issue, get an O2 spacer to get through emissions and then you can take your time to figure out what you want to do with it.

I had the same code, had an exhaust shop look for a leak, and couldn't find anything. I couldn't find a leak either, It basically just needed a new catalytic converter but I'm not willing to do that when I can fix it for $5 with a spacer for an intermittent code that doesn't effect the operation of the car. Catalytic converters wear out and lose effectiveness, and your car is over 14 years old.

You can spend a lot of money replacing the exhaust with aftermarket Chinese stuff, spend REALLY big money with Lexus factory catalytic converters, or just put an O2 spacer in there and keep driving without issues.

Considering your car is worth, I would just do the band-aid approach and save that money for other repairs.

Tom57

You can spend money, time and labor to replace the catalytic converter on your '02 LS with 100K miles, (ignoring advice you received in this thread) because your "buddy thinks it's the cat" only to have the problem unresolved. My final post here is to urge you to do more research and you'll find others who solved the P0430 problem by finding the source of the Y-pipe leak and either replacing the Y-pipe or having it welded or otherwise repaired. Or, if you insist on replacing the cat, replace the Y-pipe at the same time.

You could be this guy who replaced catalytic converters multiple times only to have P0430 remain >
http://us.lexusownersclub.com/forums...ow-what-to-do/

Or this > http://us.lexusownersclub.com/forums...0420-on-ls430/
Edit: Or > https://www.clublexus.com/forums/ls-...placement.html

MR ED

Thanks for the information again, Very helpful and informative.

For the 02 spacers are they universal?

I found this one on amazon https://www.amazon.com/Blox-Racing-B...ords=02+spacer does that work?

Thanks again .

Jks24

Yupp they are universal man and those are the ones i was talking about.

Coulter

If you can, either get a low profile one or better yet, one that has a "bend" to it. Some are like a 90 degree or 45 degree offset.

I remember the added length of the spacer with the O2 sensor being a tight fit with the universal one I got, but it was longer than it needed to be.

The threads should all be the same.

And then reset the ECU with either taking the battery cable off overnight or if you have a simple OBD 2 reader you can erase the code.

You then can take your time and figure out what's causing the code rather than just throwing lots of new exhaust parts at it.

MR ED

Thanks for all the information. I'll post results once I get it installed.

hyperopt

The catalytic converter normally should last for the live of the car. It dies mostly because something else is not working correctly and causing the catalytic converter to overwork and destroys itself. If you don't find and fix the root cause, the newly replaced catalytic converter will eventually meet its early death as well.

StanVanDam

A pinhole or hairline crack can cause a P0420/P0430 (left/right). Two common locations of these very small leaks are 1) covered by the heat shields - remove them and then check around the entire pipe for leaks and 2) any of the 3 Y-pipe gaskets.

It is very unlikely that the catalyst is bad. Installing O2 spacers doesn't address the root cause of the problem and isn't worth the time or money. An extremely miniscule exhaust leak will cause this code.

Many people including myself have had this code. First I replaced a gasket at the front of the Y-pipe due to a small invisible leak (have a helper cover the exhaust pipes temporarily and hold a piece of paper at the gaskets to feel the leak). 1-2 years later, the code came back and the cause was a small crack underneath the heatshield.

Instead of patching the crack, I opted to replace the entire Y-pipe with an aftermarket pipe w/catalyst (you can find them for $200-300), installed OEM gaskets instead of the included gaskets, and did not reattach the heat shields. Do not use aftermarket gaskets - it is well-documented that they will fail (and even small independent shops don't trust the aftermarket gaskets).

For everyone who drives on salted roads, and everyone who doesn't drive over dry grass, take the heatshields off immediately to avoid this problem. (Salt)Water gets trapped between the heatshield and the exhaust pipe and corrosion becomes greatly accelerated.