Pulls slightly left on acceleration, slightly right on braking. Just had alignment done. Brakes are fine. Guessing it's a bushing of some sort. Can anyone tell me exactly what part is the most likely culprit?

 

Make sure all your tire pressures are correct.

 

Definitely check all your tire pressures.

 

So, was it low pressure in one of your tires?

 

That behavior is an exact symptom of low pressure.

 

Sorry guys, tire pressures are good.

 

My last car had this problem and it was the lower control arm bushings. That car had a macpherson strut configuration; I don't know anything about the double wishbone suspension in the S2000. Does it even use control arms?

 

Please double check the tire pressure, especially in the rear.

If that's really not it, it could be a worn suspension component like an a-arm bushing or very worn wheel bearing. This can also occur if the suspension adjustment bolts are not tightened properly. I mention this because you have just had an alignment, but the bolts have to be pretty loose for this behavior.

 

True. Check the alignment cam bolts -- especially the ones on the rear toe-links. I had a guy that had those loose and his car did very unpredictable things as the rear toe constantly changed.

 

also make sure tread levels on rear tires are equal.