I have a 2003 Ford Expedition XLT 5.4 Liter. In January 2023 someone punched a hole in my gas tank and put sugar in the gas tank. I had the fuel tank and fuel pump replaced as the sugar caused the fuel pump to fail. When I got the car back from the shop, she still ran very rough for a while. Often times I was not able to get over 30 MPH and I was at the time getting P0171, P0174, P0300, P0302, and P0306 error codes. I took the engine apart and replaced all of the spark plugs with brand new plugs and cleaned out the injectors as best as I could and ran Techron through the system several times. I also replaced the fuel filter.
Since that time she's been running a lot better and for the most part I do have power back and am no longer getting those codes. I am however getting a P0402 code and the hoses that attach to the DPFE sensor keep blowing off. I've replaced the DPFE sensor and the DPFE hoses and replaced the EGR Valve and the EGR Solenoid. The DPFE hoses still keep blowing off and the Service Engine Soon light keeps coming back on with the P0402 code.
I am getting to my wits end with this thing as I cannot figure out as to why those DPFE hoses keep blowing off. That P0402 code only seems to come back on after one or both of the DPFE hoses has blown off the EGR Line.
I'm wondering as to what else might be causing this problem and as to what I should be looking at. I've tried everything that I personally know of to resolve this issue and it keeps returning. It's been suggested that there might be a restriction in the exhaust and at this point in time I'm starting to think that they might be right.
I don't want to have to replace the catalytic convertors if I don't have to. I'm even considering trying some Cataclean in the system to see if that works to solve the problem.
I'm wondering what your thoughts and suggestions might be to solve this issue and as to what else I might need to look at.
Well I would assume the EGR valve got blown and it's sending too much pressure and blowing it out. I'd start there. Sugar could have jammed that up
I had the fuel pump and the fuel tank replaced in March. Shortly after I got the car back from the shop, I replaced the fuel filter. I then replaced all of the spark plugs and cleaned all of the injectors out as best as I could. I've also replaced the DPFE sensor, the DPFE hoses and just recently I replaced the EGR valve and the EGR solenoid. There should be no problems with the DPFE sensor, EGR valve or the EGR solenoid as they are all brand new. I thought when I replaced the EGR valve with a brand new one that the P0402 code would go away, but it hasn't. That makes me wonder and think that maybe the exhaust is restricted and that is what is causing the DPFE hoses to blow off. As of yet, I have not tried running Cataclean through the system to see if that helps, but I intend to do that just as soon as I get the money to buy the Cataclean.
I'm even considering trying some Cataclean in the system to see if that works to solve the problem.
If the catalytic converters are that plugged up the Cataclean is unlikely to do any good. A back pressure gauge can be used to see if there is an exhaust restriction.
https://www.youtube.com/watch?v=qJTmddbOxMk
How to Clean Out the ENTIRE Fuel System (Vandalized with Sugar in Gas Tank)
https://www.youtube.com/watch?v=tRM-n15tuXs
