Hello. I own a 1995 GMC 2500 pickup with 5.7L V8 and it was running pretty good until recently. I had "Service Engine Soon" light come on. Would barely make it up a hill, but ran as usual down the next hill. Now it's hard to start and won't idle. Checked codes and error codes 33, 42, and 44 are displayed. I don't see any vacuum lines disconnected. Been watching youtube.com videos but need a place to get started. I see one connector with nothing conntected to it but I can't find a mate for it. I'll include a picture. any help greatly appreciated.
Picture is at the link below. It wouldn't share inside post for some reason:
Picture is at the link below. It wouldn't share inside post for some reason: