Help with 'check injectiom system'

Hi, I've searched and can't find anyone with the same.

I get this intermittently on acceleration, service icon once revs get higher. Has got more frequent.

Cannot tell any change in performance and have no issues, but it puts on the sevice light and prevents cruise control. My code reader will clear the code but claims there isn't one.

So far I've replaced two map sensors one on the manifold and one on the intake pipe at front.
In terms of help:

* are there any other sensors I should be looking at?
*is paying for a renault clip reading worth it, or will I get vague info back?
* what can more experienced people recommend be my next steps?
* i have some oil around the left most injector on the top of the engine, not sure if thats related or an issue it is an old car. Also have some slight pil around the furthest right one too, but seems light.
* spark plugs are about 5000 miles old at bedt, 1.5 years.
* zero other issues

Any help massively appreciated, as I don't want to start buying and replacimg stuff to no avail!

Thanks