I am a newb to diesels. Truck runs great and has a new 12V motor in it. I have searched many forums looking for similar issues. It doe not act fuel related...Here is my issue....Drove it to the store and when I came out to start it, the engine would only run with the starter cranking and would die when the key went back to the run position. However, when I gave it some pedal, then the truck stayed running when the key was returned to the run position. Truck seems to start normally a day later. The issue I have is when I let off the throttle, the idle will stay high for a moment (1100-1200 rpm) before it drops to normal. It does not matter if the truck is in drive, park or moving down the road. So when I am coming up to a stop sign and take my foot off the accelerator, the engine RPM will drop and the I get an little burst of rpm then it will hang out at the 1100-1200 range for a second or 2 or maybe longer before it drops to the normal idle.Any ideas what to look for??I was thinking the TPS controlling a low idle solenoid but not sure if this thing even has a low idle solenoid.