Q: I went to Auto Zone to get the code on my check engine light, is it the same as going to an auto shop?

asked by on December 22, 2016

Check engine light is on, got a code of PO455, is that the same code I would get if I went an auto shop

My car has 54000 miles.
My car has an automatic transmission.

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Hi there. That is probably the same code you would receive from a repair facility. However, that does not provide a diagnosis. The code is only used as a direction for the diagnosis. The computer monitors operating parameters against a preset value range. When the operating condition falls outside this range a code is set. The computer does not know the what, how, or why; only that the operation is outside the specified parameters. This is where the knowledge and experience of a qualified technician with proper diagnostic tools becomes invaluable. There is nothing more expensive and risky than replacing parts without a proper diagnosis. I suggest having a qualified technician perform an inspection to avoid replacing parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.

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