I dont know if it will run rich just with the AU injectors. because you have not changed the fuel preasure. I think he ment it will run rich with the AU injectors because they have 4 points for fuel to be injected from in one injector. I think the AU injectors are ment to be more fuel economical I dont know for sure, the reason for 4 points on one injector could be the points are smaller creating a super fine mist of fuel than that of the 1 point per injector on a EL/EF injector.

Injectors are like a tap. The bigger the tap the more fuel can get through.

Having a 'fine' mist of fuel equals better fuel cubustion which equals more economy.

This also explains rough idle also as the injector becomes blocked not enough fuel gets through. This is bad btw. I would recomend getting them cleaned by profesionals that use a sonic way of cleaning...I cand remember if its called ultra sonic or sub sonic, something like that. Basicly making them good as new. Buying second hand injectors could already be on the way to being cloged.

You can take the injectors out yourself just be careful and when you get them back you can put them in again. The guys that clean the injectors may replace the o rings too, remember to lubricate the o rings before returning them to the fuel rail, I think a small amount of 15/40 oil will be ok.

Ps. check the air filter is clean also and reseting the ECU is also what I would do before and after if you get the injectors cleaned.

One more thing...If you have removed the manifold and put it back on do it again. Most likely have a small gap sucking in air. Check vacume hoses at the end of the intake manifold. Spray CRC around ALL the manifold gaskets.

I think air leak and not enough fuel are up there with the first things to check.

Good luck