The good news is that testing a misfire code, or misfire codes, or a rough idle condition is not that hard and it's something you can do! In this tutorial, I'm going to explain in some detail the most common causes of misfires and misfire codes (P0300, P0301, P0302, P0303, P0304 -OBD II equipped 1.8L Toyota).
Solder flux is a type of metallurgy component used when soldering two metals together. The flux is an inert substance that prevents the formation of metal oxides at extreme temperatures.
What the flux does, when you heat a workpiece, is it reacts with these metal oxides that are forming with the temperature and exposure to the air, that tend to interfere with the metal-forming process of soldering.