I have had my excursion for almost 4 years, I love this truck. but lately we have been having issues that we haven't been able to figure out. First it has about 390K miles on it.

I ALWAYS have to plug it in. it could be 90 degrees out and I still have to plug it in. if it Is plugged in normally it will start fine. but then when I go to drive it, it wont have any power until I get like 2 miles down the road. you can push the pedal all the way down and it will go like 10mph. but ounce it warms up its fine. if I forget to plug it in, I will have to plug it in for about 2 hours and then it will start hard and run really rough for about 10 min. And it will blow greyish smoke out the exhaust.

But now I'm having the issue of keeping it running. it will start and run for 5-15 min and then quit and I have to wait anywhere from 10min - 1 hour to start it again.

 

If them are the original injectors,Your likely due for New or Rebuilt,there could be more Problems to work out as well,Somebody with more Knowledge on this will be along soon

 

Do you have gauges? If so, what can you monitor? Fuel pressure is a must and you'll have to rig up a manual gauge because your PCM does not monitor it. Have you done the Hutch mod? The in-tank screens can clog. You can test to see if they are clogged by removing the fuel line from the tank side of the fuel pump and blowing low pressure air back into the fuel tank. Remove the fuel cap first. If it runs fine after this procedure, then you'll know.

Are you getting any check engine or SES lights?

Do you have a diagnostic tool like Forscan? If not, consider getting it. We need all of the information that you can provide.

Link: http://www.ford-trucks.com/forums/14...the-cheap.html

What is your oil level? What oil are you running? Full synthetic 5w-40 will be somewhat to very helpful for tired injectors. Valvolene Premium Blue Extreme is currently accepted by Ford as having passed their wear test within the CK-4 spec. There may be others.

When is the last time that you changed your fuel filter? Was it black in color? If so, you likely have low ICP due to the o-rings being worn out on the injectors.

Check your ICP sensor, drivers side head up front just to the right of the valley, by unplugging it to see if there is oil in the connector. If so, it is dying a slow death. Whether there is oil in the connector or not, leave it unplugged and see if it starts easier and runs better. ForScan would likely diagnose this.
Low ICP will definitely show up in Forscan.

Your IPR could be dying as well. We could possibly gain that info from ForScan.