Shaking at idle only when engine is warm

It's time to see a mechanic. There are lots of possibilities, like Faulty oxygen or mass airflow sensor, Clogged EGR valve, Bad spark plugs, Idle air control valve problem, Fuel delivery system problems, and even a Malfunctioning transmission.

I have taken it to the mechanic, they could never get it to act up for them. They put 150miles on it trying to get it to do it again but it wouldn’t. I have replaced my vent solenoid, purge canister valve, my fuel pressure sensor, my charcoal canister. All the mechanic told me to do as most of them are inexpensive. When I replaced those I had a check engine light with codes for a random misfire, high fuel pressure, and a I forget the other one but was for the fuel vent system. Now there is no codes. Truck drives fine until I sit at a light to long, or park it that’s when after some time it starts to bog and like it’s starving for fuel. Today the battery voltage dropped from about 16 to 14 while it was having the bad idle and my ac stopped blowing cold. So I shut it off for like 5 minutes and started it and bam was just fine again. I couldn’t wait for it to do it again because I had to go back to work. But that’s why I’ve come here to see if anyone else has had this issue because I’m just at a stand still with it now.

Fuel pressure regulator? The high fuel pressure code is a good clue. Are you seeing any black smoke from the tailpipe when it acts up? If so it's running rich. That should set a code sooner or later. When was the last time you had a tune up? If you have over 100,000 miles on the vehicle it's overdue. Hope that helps! Jim

I do not see any black smoke, the codes were cleared when I took it on and none have come back. It has at 286k on her right now. I think I will try that next although it isn’t doing it all the time and there is no code it’s the only part I haven’t done before getting to the expensive parts