It's hardly noticeable even when cold, but at light throttle start on a level there's 2-3 slight "pulses" through the drivetrain as the clutch engages. It disappears quickly as it warms up and the clutch is perfect otherwise.

I'm not even sure if it's clutch, fuel, emissions or something else. Any thoughts?

 

does it only happen when you press in the throttle or when letting the clutch out (in gear) try on a flat road, slowly letting the clutch out in 1st, if it does this when your letting out the clutch its probably worn out from:

1. being burnt too often, leading to warping and un-evenness.

2. leaving it in to long or down shifting a lot thats fairly hard on the clutch and comparable to reason #1.

my old man's honda 87 civic si's clutch has been toasted and does the same thing 2x more harder. It makes for a bumpy-ish ride, and it has'nt been replaced since me and my little sister learned how to drive like 7 years ago. it only gets worse but very slowly if you can drive without being bothered to much you will be fine, but at a certain point it will affect your shifting.

 

Only happens when cold and with light throttle, normal start on a level. A firmer launch hooks right up, no sign of slip or smell ever. Prolly nothing to worry about, my first FJ did it too.

BTW, funny avatar!

 

Could be oil on the clutch plate. Do you have a leaking main seal? This happend to my old XJ.

 

Hmm, good point. I'll slide under and take a look. Routine oil level checks show none missing between changes, though it wouldn't take much to cause slip.