i have changed the fuel filter and it is still doing the same thing losing power when i give it more pedal can you help me. thew truck is a 1986 nissan D21 pick up with a four cylender with eight spark plugs it has about 58,000 miles on it i have even changed the plugs and still the same thing what should i do next HELP i need it i can't donate this time i am not working i need the truck to make money so please help me . please respond to me!

Your problem sounds like a bad ignition coil or a bad coil firing module.

If you disconnect the coils one at a time with the engine at idle (the oval plug at back of coil, NOT the high voltage wire) and if the engine dies, you found your bad system.

Try switching the module your coil is plugged into with the other module. If the problem changes sides, the module is the problem.

Your engine should idle with either coil disconnected, at a lower speed however.