I've got a 03 mustang gt with a 4.6 V8 and the battery went dead so charged it up and now it runs but only the passenger side of the engine is running the driver's side header stays cold engine barely runs and is rattling really bad anyone else ever had this problem
Was driving the car around town came home Park in the driveway and the car stayed there for 2 day's then I went out to start the car and the battery was dead I charged it up and now it barely runs and only the passenger side runs valve train rattles injectors are firing plugs look good just wet with gas coils test out good verifyed they are firing and no codes unless I unplug something
The injectors all ohm out between 14.2 and 15.5 it has good spark on all cylinders and coils ohm out good I cleaned the entire intake air system car only has 80,000 miles on it only things not stock are the ceramic coated headers and the flow master cat back exhaust
You had better check the camshaft on that bank
The pressed on camshaft lobes used to come loose and the rocker arms could break
That should be associated with some valve train noise so a long shot
Check the compression on one hole of that bank (the timing chain may have jumped time)
Good luck
If you are lucky it is just a shorted out radio coil condenser or something stupid and cheap
Possibly even fouled plugs