Purple line 2/3 the way up on engine # 4 EGT on the EICAS screen????

I may have accidently discharge # 4 fire bottle causing # 4 engine to shut down. I reset the bottle and had difficulty restarting # 4. I had to change aircraft and come back to the 744. All engine were then running, now I notice a purple line 2/3 the way up on # 4 engine's EGT. N1, EGT, Oil pressure, Oil temperature, Oil Quantity and Vibration are all normal. I have not restarted FS9 and I am continuing on with the flight. Any ideas???Thanks,Ken