If your detector is 8 years old, then yeah, it's probably due to be replaced. Mine went after just 6 years and started giving false alarms. I finally unplugged it, then replaced it before our next trip. No more problems now.
Mark & Joyce Noeltner along with Chico & Cricket the Chihuahuas
2005 Fleetwood Fiesta 26Y
2001 Jeep Cherokee Sport