Before suspecting a pedal, check the more frequent problem. Undertorqued crank-arm bolts. You can check this without a torque metering wrench, but I would reccomend investing in one since they can be had for about 40 bucks. The spec for most cranksets is in the range of 35-40 ft-lbs. It is a lot harder to overtighten than it is to under(where the damage is). So tighten with a good hard force, on both sides, then ride again. Chances are, that was the issue.
If that was not it, then the type of pedal has to be elaborated on.