1996 chevy 1 ton 6.5 diesel. Replaced the apps 2 months ago because it was slowly messing up and finally quit. Now my truck is acting VERY erratic. In the morning,when I take off,if I barely press on the pedal,it's like I floored it. I let off and it goes to an idle. It does this for about an hour( I look like an idiot going from 750 rpm to 3500) and then it only does it above 40 mph or so. At 40 mph,when i give it gas,it's again like i'm flooring it and when I let off it goes to about 1000 rpm. It reminds me of a drag racing car taking off. Also,the trans is shifting very fast(in drive by 20 mph) and is slipping. Mechanic checked the apps and it showed no voltage going to the black/yellow wire where it is supposed to have 5 volts. THEN I replaced the apps with the bad one and it now works....same problems,but it works. Checked the voltage at that same wire a week later and now it has 5 volts somehow. The only codes I have are 1214 and 1216. HELP!!...I've tore out almost all of my hair!