92 3.0V6 4Runner No power under load

[I have changed,spark-plugs,wires,cap,rotor,air-filter.set time also new cat,muffler.and tail-pipe.Has some power 1st thru 3rd 4th weak 5th none.

I heard they are built that way mean that it won't go fast, only for offroad, but if you upgrade the ECU it might go alittle faster but I'm just guessing that will work and did you change the gas filter yet? there are some performance injector for these vehicle but also I haven't try them yet so gL on your 4runner..

Check the compression first thing. Run some injector cleaner like Chevron Techron through the gas tank. Check the ECM for codes.