typeRv4

1997 Type R - v4
Walbro fuel pump - oem regulator (fuel pump fitted after remap)
Power FC
Nur spec catback
Hyperflow tmic (add just recently)

The car seems to have intermittent issues regarding idle and twice in the last 3 months cruising at lowest revs in 5th - engine died and cut out completly.

1.Sometimes - on startup with the ac on - the idle tends to hunt around abit - did this imediatly after the remap and before the walbro was fitted. More an irratant than a prob. May not be related to other symptoms.

My thts till recently probably just needs a better map for idle but then later

2. Sometimes it will not start first try - it sounds like its fired but then dies. Hasn't done it for a while but did it today. Then started second go fine.
In the past its taken quite a few gos to start. Even done this when car has been running then stopped for an hour - so probably still warm. Again a rather intermitant problem.

Only done this say 3/4 months after fuel pump installed.

3. Twice - today and three months ago - engine cutout whilst in 5th but not going my usual 3500rpms - slow traffic so just ghosting along maybe 2500rpm for quite a while. Not how i normal drive lol.

First time - felt engine die - and we just rolled to side of road very surprised. Restarted car - went fine. Never did it again till today.

Today it did the same - but this time i selected a lower gear / clutch and restarted on the move. No problems in 4th. Back in 5th 2/3 mins later started sort of missing / running rough. Back into 4th car was fine. Tested at higher revs in 5th was fine.
Was fine in 5th for the rest of the day.

I did note on the pfc commander first stop after the cutout - when i stopped 100% injector duty recorded. Very surprised never ever seen that before. Didn't do it again. low knock levels recorded.

Car ran fine the rest of the day.

Now im wondering if these are symptoms of the oem fuel regulator on its way out. Not coping with the extra pressure of the Walbro ? Too rich causing the poor starting at idle and cruise - both low fuel load.

Or maybe a temp coolant issue - as today was cooler than normal.

Or something else altogether - AFM ?

Thoughts ?