No power, slow start, poor shifting

I am experiencing a lot of trouble with my 2000 blazer. It has about 90k miles on it, and acts really doggy on the interstate. Also, it will only start in the morning if I let the pump prime first.

I'd like to try to fix the problem myself, and have a chilton's manual on its way. Can anybody tell me how to change the fuel filter?

What else could be wrong? Has anybody had trouble with injectors, fuel pumps, etc.? The air filter is clean, and the engine actually runs smoothly (just without the original oomph). I have no idea how much horsepower I am losing, but it is definitely noticable. The transmission does not want to shift right away from 3rd to 4th (my tranny mechanic told me the computer wants more hp before it shifts).

Any information would be greatly appreciated.
Thanks in advance for your help!

Todd

How long since the fuel filter has been replaced? Have you checked fuel pressure?

How is your coolant temperature when the truck has been running for a while?

Chilton's manual will tell you how to change the filter.

Any check engine lights? Smell of rotton eggs?

Coolant temp is fine, no check engine lights. No smell, no smoke, etc.

I'm pretty sure its either the pump or the filter. As far as I know, its the original fuel filter. I have never changed the filter since I have owned it (bought it in 2001 with 19k miles, so the filter has at least 70k on it). My poor maintenance aside, I'm sure at least a new filter is necessary, just don't quite know how to do it.

Remember, you always let the pump prime before you start an engine.

Filter should be on the inside of the driver's side fram rail.