2002 mazda tribute, manual 4 cylinder surging after car start & while sitting at idle.

Right after I start the car (start up
seems like it's hard for car to start
sometimes) I release the clutch and
the car surges very noticeably for 5
seconds or so. After that it surges
very smally sporadically.

When I'm driving if I get to a cry low
speed in 1st gear there is small but
noticeably vibration and surging.

Any ideas? The entire clutch and
flywheel was replaced about 10
months ago and I haven't had any
problems with this. Could it be the
battery? When I start the car with
lights on, the lights will dim when I hit
ignition key.

Thanks for any help! This has only
started happening a couple of days
ago.