Hey guys I have a 2004 F150 5.4 and ever since I changed out my spark plugs I've had the battery light go on. I've replaced the battery and 3 alternators and a starter and none of that was the issue. I run at nearly exactly 14 volts which is about .65 volts lower than I should. I've tried moving wires around to see if it would spike but I get nothing . I also took the ground wires off and tried to clean it up just in case and that did absolutely nothing.Please help.

Thanks