IS 500 - CEL problem and update
12-07-22, 07:57 AM
#631
Lead Lap
Thread Starter
^^ For what it's worth, I don't think I have seen a 2023 have the CEL problem so far. I still think the 2022s that had the problem were associated with a bad batch of gaskets and depending who got them or not. So far, and knock on wood, I have not had a single issue with mine. This is an amazing car and if you have any thoughts of getting one, don't miss your chance.
12-07-22, 10:27 AM
#632
Driver School Candidate
same here wthrman2, no problem as of yet for my 22....crossing fingers 
12-07-22, 10:34 AM
#633
Pole Position
12-07-22, 12:08 PM
#634
Ditto, I am coming up on 1 year of ownership, a little over 4k miles, and no CEL. If it does come up I will get it fixed and keep enjoying my USBeautiful car!
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DLPTony (12-08-22)
12-12-22, 02:33 PM
#636
So, my dealer told me that my IS 500 already had the cel issue fixed and the codes were caused by my aftermarket intake. However, I have been running the aftermarket intake for about 1000 plus miles before the issue occurred. When I get it back on Wednesday, I’ll continue to run it without the intake to see if the issues return.
12-12-22, 02:37 PM
#637
So, my dealer told me that my IS 500 already had the cel issue fixed and the codes were caused by my aftermarket intake. However, I have been running the aftermarket intake for about 1000 plus miles before the issue occurred. When I get it back on Wednesday, I’ll continue to run it without the intake to see if the issues return.
12-12-22, 04:33 PM
#638
I think it’s because your aftermarket intake allows for more air into the engine, so that would mean that you have to adjust and remap your ecu tuning so that the air/fuel ratio is correct, thus tripping your CEL. If this is the issue, you’ll probably notice that over the next couple thousand miles, you’ll use up more fuel and/or make less power because the ecu is assuming the old oem intake is on there and it has account for that. So without a way to tune the ecu yet, I would stick to stock until then. It does take several hundred miles more or less to trigger a CEL for something like this though.
12-12-22, 06:01 PM
#639
I think it’s because your aftermarket intake allows for more air into the engine, so that would mean that you have to adjust and remap your ecu tuning so that the air/fuel ratio is correct, thus tripping your CEL. If this is the issue, you’ll probably notice that over the next couple thousand miles, you’ll use up more fuel and/or make less power because the ecu is assuming the old oem intake is on there and it has account for that. So without a way to tune the ecu yet, I would stick to stock until then. It does take several hundred miles more or less to trigger a CEL for something like this though.
12-13-22, 05:33 AM
#640
Might have them actually check the alignment of the exhaust system where it meets the troublesome gasket. On my ‘22, they first replaced each bank’s o2 sensors, the CEL came back each time and they then replaced the gaskets. CEL came back yet again at which point Lexus flew someone in to look it over, and he realized that the exhaust system wasn’t aligned properly. The gaskets being the weakest link were therefore were taking the sacrificial brunt of that misalignment. Sounds like they used some brute force to make things properly flush at the gaskets but realigning the exhaust system seemed to end the problem.
Maybe yours has the same exhaust misalignment issue? If so it’ll keep blowing gaskets until the root cause is fixed.