You are highly recommended to check the
Spark Plug Wires when replacing spark plugs on 1998 and earlier 1.8L as well as 2001 through 2012 models. In order to do this, you will need specific tools such as a spark plug socket that would prevent damages to porcelain insulators, various extensions, a gap gauge for gap adjustment and optionally, if wire boots are stubborn; - use of a plug wire removal tool. Always let your engine cool down before beginning work on the spark plugs.This is where you get new ones, adjust their gap and install one at a time in order to simplify the replacement process. Remove the plugs after cooling the engine. While waiting for it to cool inspect them for defects or check and adjust gaps if necessary.Inserting New Plugs- remove the spark plug cover so that you can access plugs.However, this should be done differently by using another type of gauge which is a wire type gauge whose side electrode can be slightly bent by turning this part of gauge body.Therefore ,extra care should be taken because Ceramic insulator break easily.They must be handled by their ends only with one holding them at their boot, never touch anything else apart from that.Use compressed air or bicycle pump if possible, clean dirt and debris out of opening above plug.If deeply recessed into combustion chamber an extension may be needed to get these out or install them.To lock these in place and avoid removing too much or less torque then use ratchet wrench.Setting up Spark Plug-To start threading without crossing holes use piece of rubber hose instead of any other tool.The twisting motion is employed when fitting the boot on new spark plug.The whole procedure should also be repeated for remaining ones while changing them one by one so as not mix up with wires.Otherwise when removed next time they might destroy thread because it might wear away when turned backward during disassembling.Then apply thin coat of anti-seize compound to the threads before and after installation of spark plugs.