Nissan Repair: Engine shudder, nissan frontier, autozone

Question
Nissan Frontier 2002
Service engine light came on and I am noticing that I am getting a shuddering from the engine at 40 mph. The truck was just given a complete tune up 2 weeks ago because it was running rough. It runs fine at under 40. There is not a los of power or any slip in the transmission but I am wondering if this is a prelude to something. What could it be? Thanks for your help  

Answer
Pete,

First you will need to get the codes to see what the computer says is going on.  Autozone or Checker will read the codes for free.  They might even suggest the part needed to correct the problem.  Since it was so close to the tuneup there might have been something disturbed during the tuneup that is causing your problem.  Check the codes and email me back...