MY IMPREZA ITS YEAR 99.version 5- uk 2000. been remaped by andy forest, ecutec3 ,decat, on sti panel air filter, misfire at 3000/4000 revs under load.

had new pfr7b plugs, new set off plug leads, swaped a coil pack and airflow meter over from my mates car but still missing under load.
seems to be in 3/4 gear coming from slow to full boost. boost controller by passed and set up manuely.

any ideas only bought this car from a scooby net user, changed these bits with no great improvent. help

is my next set to get thus pluged in to a computer ??