P1200 GMC - 2001 yukon denali. what triggers/gives this code to come up

Question

also have lean bank 1 and 2 codes. found and fixed pinhole leak gas line. i have verified vacuum good to fuel regulator, repaced regulator, have 55 psi w/ key on eng. off. switched coils around, verifiedand switched plug wires around, done compression test on cyl. 3 (140 psi) switched plug around found and fixed vacum leak by egr. perfpormed wet test around/under intake as best icould (no change). ihave had 2 diagnostic tools on first one only showed lean bank 1 and 2 but not until after the misfire code comes up (cylinder 3). diagnostic now on said i have p 0200

Answer 1

Hi there

This code is pointing to a bad fuel injector or injector wiring harness

P1200 GMC - Fuel Injector Circuit

Read more: https://www.autocodes.com/p1200_gmc.html