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Q: My engine is running too lean

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I switched over the stock air intake with a custom one from Takeda. I have been getting a code saying the engine is running too lean and that I should clean the MAF sensor. I did that, but the code came back. I'm using premium octane gas and I'm wondering if the higher octane gas could be causing the problem. Is that how octane works? Would a high octane gas in a normal engine cause it to run lean? Thank you!

My car has 35000 miles.
My car has an automatic transmission.

Hi there. The high octane gas should not cause this; the new air intake definitely could, though. With more air entering the engine, the computer sensor readings are going to be thrown off. I would recommend that you first make sure that the new intake is secure and that there are no air leaks. I would also suggest that you confirm that the air flow sensor is installed correctly. If all of that is fine, in some cases you will just need to drive the vehicle for a while to allow the computer to adjust to the air capacity of the new intake. If you want to have this lean code looked at just to make sure that there are no other issues going on, consider having a certified mechanic, such as one from YourMechanic, diagnose your too lean condition for you.

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