Lacks power, poor MPG and codes P0171, P0174, P0300, P0302 and P0306?

Hi Everyone,

I'm new here. I've got the vehicle listed above XLT model. I'm having problems where it lacks power and is going through a lot of fuel. The check engine light is on and the codes that I've been getting from it are P0171, P0174, P0300, P0302, P0306. I'm trying to figure out as to what might be wrong with it so that I can get it fixed.

Up until January 2023, the car started and ran perfectly. There were no problems with the car. Starting at the end of January I started having problems with the car. First, I discovered a hole in the gas tank which was apparent sabotage. I plugged that hole with a fuel tank repair kit that I had on hand and at first that seemed to solve the problem.

I went to Walmart one night with a friend and when we were ready to leave, the car would not start. I had the car towed home and then I had it towed to a shop where they diagnosed the crank but no start problem and told me that the fuel pump had gone out.

I ordered a new fuel pump from Rockauto and a fuel tank from a salvage yard and had the shop replace the fuel pump and the fuel tank. They told me that when they were doing the work, they discovered that someone had put sugar in the fuel tank and said that was what caused the fuel pump to fail.

Both the tank and the fuel pump have been replaced and I have the car back in my possession. I, however, am having performance problems. The check engine light is coming on, I'm getting the codes that I mentioned and she's acting like it's in limp mode. It starts just fine, but she runs very rough and is very slow to go when I go anywhere with the car. I've replaced the fuel filter thinking that it might solve the problem and I've run Techron through the fuel system as well, but that hasn't solved the problem.

I've looked under the hood and found that there were a couple of hoses that connect to the DFPE were disconnected. I also found that one of the ports on the DFPE was broken. I've ordered a new DFPE from Rockauto and some new hoses as well and am currently waiting for them to be delivered to me.

I'm trying to figure out if there is anything else that might be causing this kind of problem that I might be overlooking and need to check. The spark plugs, coils and injectors were all replaced in 2021 with brand new parts.

Up until January of 2023, this car has started and run perfectly without any problems. Now all of a sudden it's acting up and I'm trying to figure out as to why.

I would appreciate it if one of you that does know about cars can give me some advice as to what might be causing this issue and as to what else I should be looking at.

I'm hoping that by replacing the DFPE Sensor and those hoses that connect to it, will solve the problem, but at this point I can't guarantee that, so I need to be looking at other parts to see if they might be causing the problem.

Any advice or suggestions that you might have would be greatly appreciated.