OK, I went to realoem.com, entered the last 7 digits of my car's VIN number, and it came up with the four different part numbers, two Bosch, and two NGK. When I enter any of these four part numbers in the part search function at Autohausaz, I get the following three choices:
Your Parts Search Returned 1 Part(s)
Does this imply that any of these three plugs is acceptable? If so, why on earth would I buy the $9 plug over the $3 plug? I'm sorry, but $9 (or $15, or $21) for a spark plug is ridiculous. As long as the specs (heat range, dimensions, etc.) match, why should it matter?