IF you car fails the emission test & has either code P0 410(air injection) OR P0 400 (EGR flow) then the inner passages inside of the cylinder might be plugged.
Here in the Atlanta area we see this problem ALL of the time!
IN some "extreme cases" the cylinder heads MUST be removed to solve the problem.
NO solvent added to the fuel system can get into these passages.
NO miracle in a can will help.

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