Spark ignition gasoline and compression ignition diesel engines differ in how they supply and ignite the fuel. In a spark ignition engine, the fuel is mixed with air and then inducted into the cylinder during the intake process. After the piston compresses the fuel-air mixture, the spark ignites it, causing combustion.
1 If your skin is too sensitive, dilute tea tree oil with some baby shampoo. Add 10-20 drops of tea tree oil to 1/2 cup of baby shampoo. Use this daily to wash your scalp and hair till you get rid of itchy scalp.  You can even massage diluted tea tree oil to your scalp.
Your scalp may itch due to several issues: 1  An allergic reaction: This is more likely if you wear braid extensions. 2  It's possible to experience an allergic reaction to the chemicals used to treat the hair.olutions for an Itchy Scalp. 1  Oil: Your dry scalp might just be thirsty. 2  Try oiling it with a natural oil such as jojoba -- which greatly mimics the skin's natural sebum -- or a lightweight product like grapeseed oil.