I was getting 19 mpg and now only 11 mpg and was down to 9 mpg. The truck has no guts at all and is just slugish. The service light is not on, no smoke, starts fine, mo miss, no shakes or shutters out of motor, no real noticable problems other than when you get on it or pull a load it feels like a 1500 gaser. and is only getting 11 mpg unloaded.
So this is what I have done.
-changed ebps and tube
-new glow plugs/ found 1 and 3 were out when changed bumped from 9 mpg to the 11 now so it helped but did not fix issue.
-check uvc harness ang connections
-fuel pressure is at 69 psi
-new intercooler boots and no leaks, makes 17p of boost
-new tranny from ford with only 200 miles on it
-cleaned and flushed intercooler
-check turbo health seems good
-no brake dragging rolls good
This is my thoughts of possable causes. We just installed new rebuilt tranny from ford (to get warranty,
$2,000). Now these issues. So I had my local diesel guy check it he scanned it and says motor is perfect and the tranny is all over the place. Which I feel they have the most knowledge here locally and I trust them. So I was taking it to ford to get it fixed under warranty. Then I stopped at my local tranny shop and had him scann it for me for the heck of it being I know him and he would do it for free. He says the tranny is perfect and the motor is the issue or its due to the fact of the 410 gears. well the gears wont justify the loss of power or mpg so didn't listen to that part. So I finaly got it down to ford they scanned it for the $90. And came back with the EBPS and 2 4 6 fail high to low open circuits. They said they would not look further into the tranny being it was showing fine until these were fixed. which I knew they were not going to fix the issue. So I replaced the uvc harness and the ebps sensor. But when I was doing it I found the the number 2 glow plub was fouled. I had just changed all plugs about 20-30 miles ago. So my question is what would cause this and if it was a bad uvc harness like ford says would that foul out the glow plug and cause my issues. Even though the old uvc harness I pulled out does check fine on a meter. So should I be looking for something else?