Since i had my car set-up at MSD in June i've been suffering from a bad splutter/misfire. After thinking i'd solved it i haven't and i'm pissed off.

At MSD i had an EVO L1 chip for 803, T34, 500 also on that day i had a new rotor arm, CPS, Fuel regulator and -31

After the drive home 100 miles it inherited this misfire issue so i have since change 3 sets of 071 plugs gapped @ .65, dizzy cap, 909 motorsport leads, Grp A Coil, 3 bar map all brand new and after a small test drive the other day it ran fine.

After getting on the motorway yesterday it started again but is very intermittent for example it would splutter then stop if keeping steady revs but as soon as you change engine/rev speed it splutters. This is only off boost as whilst on boost it is like an absolute rocket and has no problems at all.

Due to changing everything on the ignition side i have starting to think is it a fuel problem??? so i've got a new fuel filter and some of that injector cleaner to try but if that doesn't cure it i am stumped. Most people i have spoken to have said it's strange i have spoken to Stu as well and he said check theirs no water on the pistons which their wasn't so not head gasket.

I would like to get it back down to MSD but i'm struggling to get time.

Any advice would be handy