I have the intermittent P0420. It probably comes every 100 miles and I just clear it with my scan gauge. But I'd rather not have it.
I have new OEM O2 sensors and new cats. Those made no difference.
Anyway, today I was reading on another forum (sorry, sometimes I stray) a posting about an 01 Lexus with a recurring P0420. A tech chimed in that some toyotas of that vintage need an ECU reflash to cure it.
Any thoughts? If a reflash is relatively cheap, I'd be willing to try it.
Edit: Here's another example of a reflash curing the P0420:Toyota ECU Flash / Recalibration with the MasterTech
I have new OEM O2 sensors and new cats. Those made no difference.
Anyway, today I was reading on another forum (sorry, sometimes I stray) a posting about an 01 Lexus with a recurring P0420. A tech chimed in that some toyotas of that vintage need an ECU reflash to cure it.
Any thoughts? If a reflash is relatively cheap, I'd be willing to try it.
Edit: Here's another example of a reflash curing the P0420:Toyota ECU Flash / Recalibration with the MasterTech
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