Help Please_AU Engine Diagnostics

[kcej]

Tried "the workshop" but was ignored bigtime. Shoulda tried here first

I have an AU3 that I bought damaged.
Seemed to idle fine, start easy, but had a flat spot on acceleration
In the two weeks I've been driving it daily, the miss has gotten worse. Also, it now takes four or five seconds and a pump to start where before it was instant, with no need for pedal
Guy at work blamed dirty injectors, but before I pull em out, thought I'd ask here.
I have a complete car that I can go the "swap a part at a time" elimination route with, but where to start, and in what order, considering both
1..likelihood as a cause
2..work involved in swapover

injectors?....coil pack?....some of the sensors?

Help please.......Keith