I have a B20vtec, when I accelerate almost half the time it jerks or is stagnate(barely pulls). Also jerks when shifting, it's hard to do a smooth shift.

Funds were low after the swap, so it's still running on old/used B20 spark wires and plugs. The distributor is from a 99 Si and rotor hasn't been changed. Still running on the B20 injectors.

ECU is P73, fuel pump is 99 Si. Running on a stock exhaust system.

Please help. TIA.