Trouble codes Mass air flow sensor, fuel pump circuit open and hard fault

My check engine light has been coming on occasionally on my 1992 Explorer 4.0 liter. When the cel comes on and I come to a stop sign the engine stalls out. If I give it gas the engine stays running, but sometimes I hear a knocking sound while giving it gas. I did the paperclip KOEO test and initially I get the code 111 then I get the codes 157, 158 and 543. When I tried the engine running test I get the codes 998 and 157, but then after applying the break the engine stalls out before I can complete the test. I see that 157 and 158 have to do with the Mass Air Flow sensor voltage, 543 Fuel pump circuit open battery to PCM, and 998 Hard fault present. So I am thinking either the mass air flow sensor may be broken or it could be a wiring issue.

Any advise on how to trouble shoot further or if I'm even on the right track?

Didn't get any responce, but in case you have a similar problem, I disconnected the wire harness from the mass airflow sensor and checked voltage while runnning and was getting around 6 volts. So i figured it must be a bad mass airflow sensor, so I replaced that and it seems to have worked so far.