If by misfire yuo mean just missing a beat occasionly at idle, then check the CO% first...they can be quite fussy. If its near standard up to stage 1, set it for around 2%...if tuned higher then tweek it up a little to nearer 3%.

Any garage that aint run by monkey's can do that for you...shouldnt cost a sight as its only a 5min job.


But really, your best bet regarding fueling set up will be a rolling road session...well worth the out lay as you'll proberbly redeem the cost in saved fuel in the long run

Stu