My car has developed an intermittent misfire at exactly 2000rpm, sometimes when car is started from cold, sometimes after a motorway run when pulling up to first roundabout after slip road. Can also run for 1/2 an hour with no misfire. Completely random as far as I can tell.
Its a 52 reg BAM engine S3 with 58K on the clock.
Misfire can be in any gear but always at exactly 2000rpm! When its playing up get the rev counter to 2000 and it will do it every time but then will clear for a while.
Over past 4 weeks I have changed:
- New OEM Thermostat and temp sender (temp gauge was at 60degrees max) this is now fixed and bang on 90 again.
- 4 brand new OEM coilpacks
- New OEM air flow mass meter
- New OEM divertor valve
- New OEM standard air filter
Fault code after misfire is 'P1297 - connection charger - throttle valve pressure drop'
Car is fine under load, plenty of boost and no misfire. Just this nasty bump at 2000rpm when it chugs along like an old tractor and nearly puts you and passenger through the windscreen! As soon as the rev counter gets to 2100rpm it clears and revs up to 7000 if you want.
No ECU warning light in the dash at all when misfiring.
Car is remapped to approx 270 but now otherwise standard.
Any help would be massively appreciated, not sure where to go next and recently burnt lots of cash on this and still no better and missing having an otherwise great car running as it should.
Next thoughts are N249 (but ran with divertor unplugged and fault still there)
Thanks in advance