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Hi everyone, just got my wife a 2006 IS350. It’s been awesome, I just have the p0420 code. I’ve checked the mid pipe for leaks and nothing, not even rust. I also changed the seals as a just because and I still get the code, it also smells like rotten eggs when you get on it so sadly probably the cat. That being the case, is there anywhere I can get a reputable manifold that is cheaper than going to the dealer? I can install it myself so that’s not a problem. Thanks in advance!
Hi everyone, just got my wife a 2006 IS350. It’s been awesome, I just have the p0420 code. I’ve checked the mid pipe for leaks and nothing, not even rust. I also changed the seals as a just because and I still get the code, it also smells like rotten eggs when you get on it so sadly probably the cat. That being the case, is there anywhere I can get a reputable manifold that is cheaper than going to the dealer? I can install it myself so that’s not a problem. Thanks in advance!
If your sensors are reading well, and you're sure its the cats, I'd consider used off low mileage ebay vehicles as an option.
If your sensors are reading well, and you're sure its the cats, I'd consider used off low mileage ebay vehicles as an option.
Thank you, I’m pretty sure 250s and 350s share manifolds, but what about the C models? I’m almost 100% sure there’s no leak in the mid pipe as there was no rust, I changed the seals, and Lexus service records show it was changed before. Now the sensors I’m pretty sure are working correctly as my Bluetooth scanner didn’t show anything crazy. But just to be sure, what exactly should I be looking for when looking at the live data?
Thank you, I’m pretty sure 250s and 350s share manifolds, but what about the C models? I’m almost 100% sure there’s no leak in the mid pipe as there was no rust, I changed the seals, and Lexus service records show it was changed before. Now the sensors I’m pretty sure are working correctly as my Bluetooth scanner didn’t show anything crazy. But just to be sure, what exactly should I be looking for when looking at the live data?
If it has an oscilloscope option, watch and see if the data swings. Something like this:
At the risk of sounding stupid, I did not see an oscilloscope option but I did have a live graphing option. Here are a couple screenshots
That doesn't look bad. Can you repeat this while at steady throttle on the highway? These should mellow out and become symmetrical. i.e. each will do its own thing but the peaks and vallies will have the same amplitude and oscillation rate. If so, the sensors are likely good.
Has this engine ever had any injector issues? Can you post the actual AFR measured from the sensors?
So this is the first time the code has come up? A few years back I went through the same thing. The code just popped up. I went through the typical troubleshooting methods you can find on the forums. Removed heat shields. Replaced exhaust manifold gaskets. Resetting the code kept it at bay for weeks. I assume as the converter deteriorated the code would be more frequent. Until finally resetting the code just triggered instantly.
That doesn't look bad. Can you repeat this while at steady throttle on the highway? These should mellow out and become symmetrical. i.e. each will do its own thing but the peaks and vallies will have the same amplitude and oscillation rate. If so, the sensors are likely good.
Has this engine ever had any injector issues? Can you post the actual AFR measured from the sensors?
Definitely, I’ll see if I can get those today. As far as the injectors I’m not sure, I’ll take a super close look at the service records. But since I’ve owned it no issues
So this is the first time the code has come up? A few years back I went through the same thing. The code just popped up. I went through the typical troubleshooting methods you can find on the forums. Removed heat shields. Replaced exhaust manifold gaskets. Resetting the code kept it at bay for weeks. I assume as the converter deteriorated the code would be more frequent. Until finally resetting the code just triggered instantly.
The code has been there since I’ve owned it, and the previous owner said it would go away on its own at times. Although it’s never done that for me. It’s also popped back up quicker and quicker over time, but oddly enough it stayed away longer than usual when I changed the manifold to mid pipe seals, and again when changing the oil cap do to it being cracked.
The code has been there since I’ve owned it, and the previous owner said it would go away on its own at times. Although it’s never done that for me. It’s also popped back up quicker and quicker over time, but oddly enough it stayed away longer than usual when I changed the manifold to mid pipe seals, and again when changing the oil cap do to it being cracked.
Post up your fuel trims if you can. I'm curious at to what they're showing.
I'd probably say the cat is done. Ultimately replacing it was the fix for me.
So this is the first time the code has come up? A few years back I went through the same thing. The code just popped up. I went through the typical troubleshooting methods you can find on the forums. Removed heat shields. Replaced exhaust manifold gaskets. Resetting the code kept it at bay for weeks. I assume as the converter deteriorated the code would be more frequent. Until finally resetting the code just triggered instantly.
Mike did your vehicle have issues that killed the cat or did it just die of its own will?
Most of these are typically good for 200k miles or more if not subjected to ignition coil failure or leaky injectors.
Mike did your vehicle have issues that killed the cat or did it just die of its own will?
Most of these are typically good for 200k miles or more if not subjected to ignition coil failure or leaky injectors.
It's hard to say since it went out probably close to 100k. I have to check my other threads. Though for one bank 1 has always ran rich for my car after sometime. So I'm going to say probably its a leaking injectors issue. Since you already know way back when I changed out my fuel filter. I'm assuming sediment made it far down stream to the injector basket filters.
Again this is just my speculation. I did pull the spark plugs on bank 1 before. They're not showing black soot on the insulator nose. Fuel trims shorts are always near 0. The long term likes to settle around -12%. Of course as I drive it will go down to -3% on long trips. Cylinders 3,5 only have light wet threads for some reason. Everything else is pretty standard.
Cylinders 1,2,4,6 are bone dry.
I have unbolted the cold start injector, and left it over night. It's bone dry in the morning. That is working as it should. Coils are good I bought a set of Denso's awhile back. Replaced cylinders 3,5 same scenario wet plug threads after some use. I've since put back the OEM.
Someday I hope to get out of this lazy pandemic spell. I'll get a borescope, and do some good ole trouble shooting lol.
And the car has 218k so that’s why I’m not doubting it’s the cat. Silly question, when looking at fuel trims what do you look for? I really wanna learn what all the live data means and how to diagnose with it lol
And the car has 218k so that’s why I’m not doubting it’s the cat. Silly question, when looking at fuel trims what do you look for? I really wanna learn what all the live data means and how to diagnose with it lol
Reputable Cat/Manifold
