My 92 Toyota p/u keeps jumping time?

I had the engine rebuilt in my 92 Toyota p/u. it's a V6 4WD. It runs good for the most part, but randomly has a jump while going a different high speeds. It also jerky jump while in other gear levels. It doesn't seem to do this jump thing in any specific gear or speed. No in dash lights come on when this happens. And it doesn't happen every day. Need help.

By jump, you most likely mean miss, and that's typically ignition related :sparkplugs,WIRES, distributor cap, rotor, check there 1st, I typically lightly spray engine with water, any wires bad will typically make motor miss, but not nessesarily

I think it's time for you to sell this car since it looks to be giving the amount of trouble. No have to attempt and replace another fitted system. it was over worked and reached it sustenance period

If it jumped time the belt or chain jumps a tooth and you could have to take the motor separately every time to fix it. If the motor has an intermittent miss then check the EGR valve, and the fuel quality.Perhaps there's water in the tank.