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Hello everyone, first post here, thanks for having me. I am having trouble trying to figure out what the cause of my check engine light is on my 1997 Ford Ranger with the 4.0 V6 4wd manual. The codes that pop up are P0172 and P0175, Bank 1 rich and Bank 2 rich. Here is a list of all the parts I have recently replaced:
-Fuel pump -Fuel filter -Fuel pressure regulator -Upper plenum gasket -Spark Plugs -Idle Air Control Valve -MAF -Air filter -PCV valve -Vacuum hose from intake tube to oil filler neck -PCV valve hose
-Spark Plug Wires
I check fuel pressure and it holds right around 30psi while running and continues to hold after shut off, and I did a smoke test through various vacuum lines, the fuel tank, and exhaust. The only place I saw smoke come out of was at the front of the air box, and the exhaust flange right after the post cat O2 sensor. I also do not smell gas in the FPR vacuum line. When I check the freeze frame data on my scanner I get the following:
Lastly when I look at my MAF sensor readings while idling, I read around 4.6 g/s (I may have the units wrong, don't kill me). I honestly have no idea what else it could be at this point and would appreciate any other feedback or suggestions. If I missed something please ask and I will answer best to my ability. Thank you
