A misfire condition and its corresponding misfire trouble code can be the result one of many different components having failed... that troubleshooting its cause can seem almost impossible. For example, the misfire code could be caused by a bad Coil-on-Plug (COP) ignition coil, or a bad fuel injector, or in one engine cylinder having very low compression, and the list could go on...
According to Spam's website, the canned meat contains only 6 ingredients: already-cooked pork (two different cuts: pork shoulder and ham), salt, water, potato starch (to keep the meat moist), sugar and sodium nitrite (a common preservative).
I think the difference is just the name - spam is a brand name. It does taste different to other luncheon meats, but that will just be down to the recipe they use. Basically the same stuff. Just as Coca Cola and Pepsi are basically the same things - both cola drinks, different recipes and tastes.