when I start my truck for the first time each day I get a 2-3 second stumble if I don't let it warm up for about 15 seconds or so....it doesn't do it any time after that during the day. It is almost like the fuel line drops pressure or something......any ideas ??

 

mine stumbles when i first start it sometimes as well...almost sounds like it has a huge cam in it for 10-20 seconds then it idles fine after that...what's up with it?

 

It probably takes the fuel pump a few seconds to fully pressurize to system first thing in the morning after the system has depressurized overnight.The rest of the time you have residual pressure in the system.

 

What octane gas are you using? If I fill up with 91 or 92 octane it takes 3-4 seconds to start, sometimes it will even die on me. If I use 87 octane it just fires right up immediately. Dunno why?