On the way to the petrol startion (fuel light on) i was waiting at a junction, the revs kept repeatedly and violently dropping to 500rpm then back to 1000rpm very quickly, it would not stop. I filled it up with petrol,(51l, so 10l was left in the tank). Started it up, revs where the same, dropping to 500 and 1000rpm repeatedly and quickly.
Quick as a flash, i popped the bonnet and unplugged the maf, started her up again, started after a few turns, then immediately stalled. Repeat 3 times, it would not idle and would not accept throttle unputs (as if it wasn't sending fuel full stop).
Plugged the maf back in, car was back to normal with the Very bad hunting idle as before.
This problem has always been happening but normally when i park as i arrive home. It seemed much worse today.
Can anyone advise? New thermostat will be fitted on saturday, along with throttle body clean and BBOB rebuild/clean (whatever necessary), then an ECU remap. but what if that makes no difference? Where do i go next?