Q: Replaced pre-cat with header. Will a 02 simulator make engine light go off!

asked by on January 09, 2018

Because I heard that the pre-cat breaks up and causes engine problems, I replaced it with a header. Now the engine light wont go off. I have had it checked and it is caused by the header. Is there away to use a 02 simulator to make the light go off. Also, several people have said that the 2006 Altima has 2 02 sensors, I only find 1. Where would the down stream be located? Thanks for your help! Brad

My car has 155000 miles.
My car has an automatic transmission.

Hi Brad. Thanks for submitting your question tonight. Unfortunately, when aftermarket alternations are made to a vehicle, our ability to offer accurate repair tips and advice is compromised, as we don’t offer tips on aftermarket alterations. You should probably consult with an online Nissan performance forum, so you can get some accurate tips from people who have gone through this same issue. By the way, the downstream sensor is always located after the catalytic converter.

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