1993 power issues
 

Okay I am about to loose my mind. My 1993 4 cylinder has this issue where you will be going along and then it seems to bog down like it is not getting enough fuel. I have changed the fuel filter. I have put a new fuel pump on it. The dealer diagnosed it as needing a distributor, cap, rotor and new wires. I did not want to shell out the $1600 for them to do all this so I got a used distributor a new coil, wires, cap and rotor. It is still doing it. The dealer said that after market parts can cause this. I do not buy that. It is not the catalytic converter as that was changed too. Any help here would be appreciated.

Thanks

New plugs also?

How does the engine idle?

What happens if you leave the trans in a lower gear or manually down shift?

Do you have access to used parts (as in cheap to buy) such as MAP and Throttle Position sensor?