Hi Bob and welcome to the forum, I have not heard pinging.
You would have to explain pinging a bit better, and where you are hearing it, and for how long the pinging goes on, just the 2 seconds or repeating a while later for another 2 seconds? Is it from the engine, is it from the exhaust, is it just to do with cooling down of parts after you are parked?
Cooling down of parts is the usual cause of noises after a run, due to the expansion of heated parts during car running and then contraction during cooling when parked, like the manifold, exhaust, heat shields come loose or not fitted right on exhaust system are usually the culprit.