Need Help

[$300Explorer]

I recently purchased a 1998 Ford Explorer w/ a 4.0 OHV. The car was said to have run but we couldnt get it started. I replaced the battery, battery ends, starter and fuel pump and got it running. It had a small miss but was running good. Then all of a sudden it started running horrible. I got 7 engine codes which were: P0155, P1151, P0113, P0102, P0122, P0104, and P1131. The Car had a rough low idle, a miss (heavy going uphill), and lack of power. I replaced the fuel filter, spark plugs, coil pack, EGR valve, O2 sensor, throttle position sensor, MAF sensor and throttle body. It seems to run a little better but then i got a code for O2 sensor again. The car still has a low idle (700), lack of power, a really rough idle, and still misses. It sounded like a head gasket but it wasnt smoking, I dont think it is a vacuum leak either. Please Help!!

 

[jmvb]

P0155 : 02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)
P1151: Lack of HO2S-21 Switch, Sensor Indicates Lean
P0113: Intake Air Temperature Sensor Circuit
P102: Mass Air Flow (MAF) Circuit Low Input
P0122: Throttle Position Sensor/Switch A Circuit Low Input
P104: Mass or Volume Air Flow Circuit Intermittent
P1131: Lack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 1

It is very unusual that you have all this codes
together.

If you had change all stuff that you say, for me, sounds like you have a harness problem or a PCM problem.

 

[RandomNerd2000]

Check for melted O2 sensor wiring, I remember at one point someone on YouTube had that same issue, caused it to go into limp mode, had similar codes to yours. If that's not it, I'd take a good look at the fuses and relays, it could be a PCM problem, but PCMs normally don't just die