I need help from someone with 4000 years of experience!!
2003 dakota 4.7L quad cab, 230,000KHMS (not miles)

MY truck has had terrible gas mileage. 6-9 mpg avg on the hud.
So i assumed the basis things, changed plugs,air filter, new exhaust, new map sensor, looked for vacuum leaks, no better results.

then opened up what is either my evap purge or my egr solenoid
it functioned properly no signs of damage or anything.
then im driving and it starts to shake at 70khms, and rough idle.
I always carry a obd reader so i plug it in and im getting cylinder 2 misfire and map high voltage.... cleared them, succesful erase. misfire came back instantly. map code gone.. then TPS high voltage appears when i get home and check again.

I then proceded to pull every single injector inspect clean replace orings,
( i checked to make sure they're all opening )
back in they went. I also pulled #2 plug and it was rough, had orange/red spark. changed the coil pack out with a spare one.
and the #4 cylinder injector had the bottom oring fold into itself and it appeared like it had been that way for years.

put everything back together fired it up still felt like it had a misfire, but no code, so i would pull #2 coil while its running, no change to rough idle.
shut it off start again to see if i had to purge more air out.
then pull #2 coil again while its running, it changes the idle, but still had the misfire..

i then changed out the plug to an old one that are in terrible shape and it ran a little smoother but still a misfire but no code.

now my radio and my blinkers and probably my brake lights wont work


And just a little side note, when it started the misfire and **** while i was driving, my mpg went up to 14-16mpg

 

Moved to the correct section.

 

This forum sucks.

 

As do you. Perhaps you should rely on facebook to solve your problems.

 

Without this forum and help received from others I wouldn't be keeping my Dodge running. Go take yours to the dealer then you can complain about how they suck!