limp mode on please help

On my ride home last night which this week has been a long commute 200 miles a day and bought my fuel at a different station than usual. Well my limp mode came on and engine light. My truck is 2005 2500 4x4 GMC diesel I think its an LLY. I do have the edge with juice. usualy ride around on #3. The truck has just under 50,000 miles on it so I think the motor is covered. But should i take the edge off before taking it to a dealer? And are their a few things I can check before even doing that. I guess what im asking is were do I start today. Any suggestions would be apprieciated.Their was no funny sounds or smells or anything but the truck has been smoking more lately when getting on it. Figured it was just braking in a little more do to the smoke hasent been rediculous. I did fuel filter and air and tranny filters about a month ago. Also can you open the petcock or the thing on the bottom of the fuel filter to drain it or do you have remove it to drain it.  

Yes, pull the Edge before you take it in otherwise you can kiss the warranty and several grand for new injectors goodbye.  On the '05 I don't think there is a way the dealer will know it was there, but wait for the Chevy guys to chime in.

If there is a petcock on the bottom of the filter, drain it into a large Mason jar so you can check for water in your fuel.  If there is any, I would dump some FPPF (you'll find it at truck stops and good auto parts stores) to get rid of the water.  You can also try some Power Service (Wal-Mart, auto section) in the white plastic bottle.  Both of these will help with that.

You said its smoking more; what color is the smoke?  You could very well have an injector or three that has headed south and the smoke color will help us give you better info.


Kris  
2006 Dodge Ram 2500 QC 5.9L - No Mods Yet
2008 Dodge Ram 3500 QC 6.7L - Titan Fuel Tank Owner