2005 5.4 navigator issues lean missfire NOBODY CAN FIX IT SO FAR!

[coreywsimon]

So here is where I'm at, I had a master tech look at the car for about a month. The 2005 navigator with a 5.4 misses at idle, pops lean codes on one bank and particularly two cylinders i believe bank 2 and cyl 3 and 5. the other time i can feel the miss is doing about 50mph when i just let into the gas pedal lightly it will rumbel with the motor missing till i give it more gas or let off of it. this is very low RPMS when this takes place like 1400. The tech did evap leak test, checked all vacuum lines, replaced all spark plugs with new ones, replaced all COP with new ones and some other stuff i forgot. Took it to ford had them hold it for a week to get it into best tech. that tech had another navigator and took all o2 sensors intake sensors like maf and swapped them with mine and still no change. The swapped the computer and still no change. they tested compression and one bank is normal like 160-170 the other bank however is 190-200psi on the compression. they preformed a leak down test and everything looked good. I ran it into another shop where their best tech looked at the vehicle and they did cam phazers to see if it was timing. this didn't fix it. I just replaced the fuel filter and that seemed to make it idle ok for a few min then right back to normal. I have read so many forms im lost and the business that did the phazers spent 15hr on it and said out of 31yrs they have never ben able to not fix something till now? please help lots of money lost.

 

[wadesdad]

Did you take a look at the fuel pump driver module? If you live in the rust belt, it is common for the back to corrode and it will cause you fits. My 2006 acted this way before replacing it. It is mounted inside the frame rail near driver's side rear tire.