Diagnostic Aids
WARNING: This page is about a different car, the 2000 Isuzu Rodeo and 2000 Isuzu Amigo. However, it is still accessible from the selected car via links, so may be relevant.
An open or short in injector driver circuit will cause DTC P0201-P0204 to set and a misfire to occur due to inoperative injector. This type of DTC will indicate which cylinder is inoperative. Long and short term fuel trims being excessively high or low are a good indication that an injector is faulty.