On the m43 generally that side of stuff is usually quite reliable.
Does the car have decent fresh fuel first of all as unleaded goes off a bit with time.
Plugs on m43 iridium 60k change
Vacuum pipes a big issue .
Firstly closely check the main rubber boots from air filter box to throttle body for cracks and splitting.
Then it starts to get more awkward without dismantling.
I will put pictures up in the morning just its dark and wet just now up here in Scotland and my zeds are outside.
So off the main pipes you will see around half way along another smaller hose is joined to it and runs under the manifold check that for same
This then goes to a piece that splits it into 4 ( this usually ok but check as well) then there is another 4 rubber hoses off this one to each injector again check for cracks and splitting.
Another piece of hose to check is at the front of rocker cover is the fuel rail pressure regulator it has a small vacuum hose that has a t piece and runs into throttle body and cant remember where else till i look

.
Start with that lot before anything else
These will help a bit Stephen.