I have a 2001 Ford F-150 5.4 litre pick up with 114.000 kms, i drove to work the other night and everything was fine, when i left to come home i started the truck and it was idleing rough. When i got on the highway it ran fine if i never went over 40 kms a hour when i went over 40kms the whole truck seemed to be shaking and then my check engine light came on, any ideas out there what could be the problem

 

Most likely a misfiring cylinder or two. Get the codes read and post them here. Then we won't be guessing about the problem. Good luck!

 

Probably a COP is going out. CEL will tell you what cylinder is going out.