May 05 Dakota 4.7 is giving a P0172 code. I’ve replaced the PCV Valve, all 8 injectors and Plugs. It still falls flat on its face when under acceleration. I’m at a loss of what to check next. Any suggestions would be greatly appreciated.

 

How old are the O2 sensors? What did the plugs look like? Especially those on the effected side.

 

They were in bad shape. I believe they are the factory O2 Sensors

 

I'd start by looking at the vacuum lines. Smoke test the intake. If that passes, I'd move on to compression test.

 

Replace the front O2 sensor. Denso, or NTK sensors ONLY please. Skip Bosch. These trucks don't like 'em.

 

Is this a good O2 Sensor read

ing

 

Rear sensors are not reading even close to the same there..... Does yours have dual cats??

 

It has dual cats.

 

Hhhmmm.... So, possibly a bad sensor, or maybe an inefficient cat..... The front sensors appear to be reading just fine though...... Could try replacing the rear O2 sensor on bank 1..... Don't know if that will fix it though. Will your scanner show what it thinks the mixture ratio is??

 

I think it will, I will have to check