2.9l ranger pops
it will do it about once every half hour or so, not very often but this shouldnt happen.
as of right now i got the timming set so i get about 1 spark knock going into high gear. i guess i could set it higher, but then i get more spark knock. yesterday i changed the plug wires, rotor/ distributor cap and not long ago the spark plugs. it has done this with the timming set where it is for a while now. maybe i just need to whind the gears a little more becouse i havnt heard it do it when the rpm is above about 2000 rpm.