I had that issue a while back, turned out to be an O2.

I dumped bucks into mine... including replacing the O2 sensor. The shop (after 3 weeks, every day) finally found it... an O2 sensor.

They say they've seen some of the aftermarket units fail... so recommend Bosch, since no one would pay the price the dealer wants. <g> BTW, mine mostly did it when it was cold, at first... then it started missing... then you could sometimes feel it when warm.

Yep,  Lower CRANK PULLEY.   Most of them wobble when worn.  It is often a sure sign of damage or impending damage.  You can often just look down at the belt while it is running.  


This method is not accurate, as the run out on a belt pulley is not as exact as that on the T-belt / crank.  

But the loss motion / movement is amplified by looking at the larger serpentine belt crank pulley.  If it looks wobbly then tear it down & check it.  Lock tite the crank bolt on reassembly

sounds like this is a  fairly common problem, too bad zuki didn't do anything to correct it, well thanks for al  the ideas. OH, I'm almost done my lightbar for a soft top, just gotta straighted the lights and add some paint, I'll post pics when done.