I have been working on my evo 8 for a while now off and on after a complete ground up rebuild. I have gotten the car started up. I have this biss adjusted and it idles perfect . Now if I push the clutch in and barley touch the gas pedal it either dies instantly or will start idiling extremely erratic and eventually die i tried driving it about a block and it’s died 7 times backfired. Any ideas on what would cause that. Thanks in advance