First of all let me say I understand this job is not fun but that's okay it's not my only vehicle. I have a 98 suburban 2500 and what are the signs that the fuel pump is going bad? At this time the issues that have me concerned is a very twitchy fuel gauge. Another sign is that I will drive it to work and after it sat in the sun for a little while and I go to start it again I turn the key and it hesitates to start. And what I mean by hesitate it's like when you go to start a vehicle and you haven't turned the key long enough in the engine just barely catches fire and then starts up if that makes any sense. Truck has 217,000 miles on it. Filter has been changed.