Engine cylinders are not firing - misfire

Have the computer scanned for code/s-you have a problem within the engine management system that caused the CEL to turn on-This is your starting point of diagnosis, finding out what's going on.

Here's the good new's most of the time when you get those code's there caused by a bad valve body supplying too low of line pressure in the transmission. That would be a external repair not requiring you to remove the transmission. You would have to get a transmission pressure gauge to test that and then remove the valve body to air check the clutch pack's with compressed air to make sure they hold.