one of the connectors on coils or injectors is loose/damaged cables, 1 coil is short, 1 injector is short, 1 spark plug is short, or the black pipe on the choke has come off (it is a black box 3inch big stuck on right side of thortle body). easiest way to check is when the start starts misfiring do the following:
1. take off the air filter box
2. start to disconnect and than reconnect the ignition coil connectors one by one
ideally when you disconnect engine should get unstable and reconnect should make it stable again, if a single coil has no affect than that cylinder is the culprit. now properly check the coil, plug and injector on that particular cylinder only. most common fault on all JDM is the connector wire is damaged and it that doesnt allow a proper flow of current hence causing problems depending on engine compartment temperature (plastic insulations expands on heating)
