Just purchased the 2007 Mitsubishi Endeavor in February this year with no issues known. CarFax came back fairly okay with no red flags. On my way to work this week, the car started to struggle to accelerate and the TCL light and Service Engine light came on. It idles roughly when started and shakes the whole time. I can get it up to 35 mph and it'll still shake, but any acceleration causes more shuddering. It doesn't shudder when I let it coast. Truly at a lost at this point!

 

I would start with a CEL scan. Might be a mis-fire, hopefully it's not one of the cylinders in the back (2,4,6), those require removing the intake manifold and a PITA to do.

 

Did you ever find the problem mines doing the same thing