My 1995 Ford ranger 4.0 is stumbling during the acceleration between 45 and 55 miles. It just started during the last rain I have checked ignition coil for resistance on the primary and secondary I have checked ohms resistance my spark plug wires check the gap on my plugs. I thought it was the maf sensor but I am getting a reading from live data via scan tool live data. I am getting a code for cam shaft position sensor and misfire. I replaced the cam shaft position sensor and erase the codes yet I have another camshaft position code and misfire code. Could this be the timing chain it has 190,000 miles.

 

Does the misfire code point to one particular cylinder?What are the codes? The timing chain likely is worn but I doubt that is causing your problem. You checked component resistance statically but ignition components usually break down under load and is a good possibility. Plug gaps should be .054... A lean miss can cause your problem( vacuum leaks, EGR, fuel delivery issues).. I would start by checking the basics such as fuel deliver, fuel pressure should 30-45 psi.. Verify that your fuel pressure is at specs at idle and under load. Has the fuel filter been changed recently?
I would check your connections and wiring associated with your cam shaft sensor. A bad sensor out of the box is possible but I doubt your original part was bad.

 

I just purchased a fuel filter yesterday I’ll put it on tomorrow. I’ll also do a fuel pressure check probably do a compression test and might will just replace the spark plugs and wires. No vacuum leaks and I just replace the EGR last year. I will post the results tomorrow afternoon thank you.

 

You might want to read up on the procedure to change the fuel filter.
You might require a special tool to remove the fuel lines from the old filter, maybe not, but you must reduce the fuel pressure in the fuel lines before disconnecting the lines. You can do this by removing the fuel pump fuse and allowing the engine to stall due to lack of fuel pump operation. Then after replacing the filter reinstall the fuel pump fuse , turn the key on and check for any leaks. Always try to remind folks not to use an electric powered drop light under the vehicle when doing this because if fuel gets on the hot bulb , sure you get the picture.

There re special "O" rings in the fuel line ends, make sure they are in there before connecting to the ends of the filter.

 

p0340 cam position sensor
p0300 generic random multiple cylinder misfire
I swapped fuel filter but same stumbling 45-60 mph but has smooth idle and shifts good. I replaced the camshaft position sensor and the code was set again.