I have a 91 Honda accord. It is a manual transmission. I noticed that the car hesitates and very sluggish when taking off. It hesitates throughout all the gears. It shifts fine. I just have to shift the gears around 3k rpms. When going up hills, it feels very sluggish.I would like to know do anyone have any suggestions on what the problem may be.

 

Sounds like you have carbon plugging up your egr ports on the intake manifold. Please see the DIY right-up...there are several links to reference. Let us know if that sounds like the problem you are having.

 

If the EGR ports are plugged up you should feel a miss or stumble around 1700 RPM while under load with the throttle 1/4-1/2 way open.
When was the last time fresh plugs were installed?
Ex model?