OT: 2000 Ford Ranger 4.0 OHV trouble codes. Need some help.

Ok I know this is off topic but I have tried some of the ranger forums and had no luck. I know you guys won't let me down. My truck is throwing codes p0172 and p0175 which means that bank 1 and 2 are too rich. That usually means that the mass air flow sensor or 02 sensors are acting up. But I have a live data scanner and I am not seeing any abnormal numbers on the sensors. Here is where I hope someone here is a ranger expert. This is a 2000 model truck with the single line fuel pump that puts out the higher fuel presssure. But..... when I put the engine in this truck back in the spring the engine came from a 96. So...... I did not know there was a difference at the time but I did not swap the fuel injectors and they are for the lower pressure system. So after all that my question is could these injectors over fuel because they are not made for the pressure. But even though the computer is picking up a rich condition the truck does not appear to be running rich. The plugs are not black. Other than the light on you would not think there was a thing wrong. It runs fine and has no drivability issues.

Any help is appreciated. Thanks!!

can you see fuel trims with your scanner ? if the long or short fuel trims are much over minus 8% (-8%) it is overfueling and if those numbers are more like -25% it is way overfueling and causing the codes. A bad Maf could cause that but if you have different injectors than it did have I would suspect that as a good starting point

I have a 2000 4.0 Ranger. In '08 one of the heads developed an internal crack that turned the oil in my crankcase to chocolate milk. I found out that this is a chronic non repairable problem. My son checked the internet and found some guy in West Virginia selling brand new complete heads from Australia (supposedly the internal crack problem solved by a better casting) for $180 each including valves, springs, etc. All I had to buy were new bolts (1 use, they stretch)and a gasket set. As of today it is still running fine with over 205K miles on it..

I'm not sure, we need to confirm this.. I just had a 2000 engine put in my 98.. I was told then that the 98 to 2001 was the same and would work on same computer..Earlier engines had a bit different set up.... Might be throwing false codes ???
There is a lot of video You Tube on "how to" for rangers

such as using the correct cleaner for MAF sensor

fordrangerforum.com may have some information.

Check out the link and do some searching there and you may find some more info. Mine needs work but I'll get to it when I have time, hopefully. Intake gaskets and leaking head gaskets were probs on the OHV/early ones, I have the same codes as you.
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