Review on 8MILELAKE Glow Plug Electrodes Removal Tool Set for M8 and M10 by Jake Hill

Victory! A broken tip can be a nightmare. This kit is the least expensive option I've found and you have a great chance of success. To avoid breaking the tips in the first place, don't try to remove the plug simply with an unscrewing motion. Instead, move back and forth, 1/4 turn, then 1/2 turn in, 3/4 out, 1/2 turn in, and so on. Most likely you will receive the connector intact. DO NOT FORCE the connector or the tip will break off. If the tip breaks off (and yours probably, otherwise you wouldn't be reading this): 1. Get this kit2. Choose an adapter and measure carefully to avoid over-drilling. Use the old plugin that is already available as a template and practice with it.3. Use LOTS of lube when threading. WD40 is excellent for this purpose. Do not attempt to cut threads without lubrication.4. Don't force anything. Properly cut threads make everything smooth as silk. Much luck! The photo shows a successful result in my situation.