I think your RVR is in partnership with Ian's (White knight). His has done almost the exact same thing today.
Still waiting to hear what he has tested as yet, but it can be traced to a heap of things from coil pack, spark plug gap (believe it or not) relays, fuel pump, air leaks, timing issues, FAIV, ECU issues etc etc, all the way to timing belt jumping teeth or stretch..........I searched my arse off today trying to help Ian out while he was on the side of the road 150km away, and the amount of crap that can go wrong and make the car have issues with idle and make popping mini backfires and running and stopping is a long one.
Eliminate fuel first. Crank while floored, smell for fuel at exhaust. If nothing Take the fuel hose off where it meets the rail, put it on a container if possible and see if the pump pumps the fuel. Ideally if you could see if it was making pressure with an FPR with gauge it would negate this test. If it's flowing, you might could re-connect the fuel line then take the fuel rail off keeping the injectors in place and see if they are being triggered.
Check if it is getting spark next. Get a hand to crank the engine and try to earth out a lead, watch for the spark. Wear rubber gloves lol
If both of these check out then it's just an issue of them not being in the right place at the right time or not doing it consistently (usually coils faff about, test ok, get hot and go to lunch on you).
This is a very crude way of eliminating the two basics.
