Originally posted by dave5000:
It is unlikely that both HO2 sensors are shot, but still possible, I imagine. I'll search for a procedure to test the ECT as well, or just replace it. If my cats are shot would I need to replace the main cat also? Or just the precats and then we see how it goes? The whole mileliminator thing scares me...is that legal? Thanks once again.
You'd just have to replace the precats because your P0420 and P0430 are directly related to those. Your main cat is further back in the exhaust system...
And technically, No, it's not legal to put mils on your car. Your O2 sensors are there to ensure your car is running at it's best and putting out clean exhaust.
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