Q: I have a 2003 toyota camry with "check engine" light on. I was told by one mechanic at Goodyear that it is due to catalytic conve

I think what the mechanic was telling you is that there are two different ways to replace a catalytic converter. The first way is to have factory type parts installed, that will normally come with the converter, and the adjoining pipe sections and flanges with them. Of course, this is typically a more expensive replacement due to the extra pieces and engineering involved. Typically, the less expensive way, is to go to a repair shop that specializes in exhaust work. They will normally cut the existing catalytic converter out and replace it by welding in a universal style converter. There are different schools of thought as to whether the universal style are as good as the factory style, and whether or not they will last as long. A low quality, and some remanufactured, catalytic converters can cause issues due to being less efficient, or will not last as long due to being manufactured with lower quality components. When it comes to converter replacement, I tend to stick with the factory parts as much as I can, as I have had better results with them, over the universal style. If you feel you would like another opinion in diagnosing and fixing the issue, consult a certified mechanic, like those available at YourMechanic.com.