Hey guys I have a 96 7.3l. This only happens when the motor is cold. About 10 seconds after the motor starts I can see the battery gauge on the dash surging up and down about 1 sec. intervals. I can hear the idle increasing with voltage at the same time. This last for about 30 seconds and then everything returns to normal. It does this every morning. If the motor is warm it doesn’t do this at all. I know it’s normal the glowplugs continue to operate after the motor starts until the gpr kicks off but this issue is new because it is as if the gpr is cycling on and off for about 30 seconds. But again it does it every time the motor is cold and never does it when it’s warm so so I’m not sold that’s it’s the gpr. I haven’t replaced the gpr yet. I wanted to get some feedback before loading the parts cannon. The glow plugs are about 2 years old and are motorcraft. The valve cover connections visually look good. The batteries are in good condition with clean terminals. The alternator is recently replaced but this problem existed before I replace d the alternator. I’ve also heard that the PCM controls when the gpr gets turned off but I don’t know how I would go about diagnosing the PCM. Any suggestions would be greatly appreciated. Thanks.