Hi, looking for some help regarding my S6 5.2 v10, been in the garage since January with epc and esp light on, car runs rough and won't go by 4k rpm, I've replaced battery, Alternator, long cable from engine bay to control module, thermostat, coils, spark plugs throttle bodies, removed Inlet manifold (all flaps intact and working as should), carbon cleaned whilst off, rebuilt it all then changed both maf sensors and still it runs like a burst a**e.
The car ran great up until January however every so often these lights would come on when cold starting, they would go off after a couple of attempts at starting whilst holding throttle down and turning key off and back on mid rev, makes no sense but it worked.
The car has had a replacement engine (40k miles on it), it's been decatted with powerflow exhaust, 2x ramair cone filters, stage 2 remap.
Really struggling to get to the bottom of this issue so if anyone has any advice I would really appreciate it, thanks in advance