hey i just recently bought my truck and its got a small rough idle, it has 113000 kms on it. im thinking that it could just be that the spark plugs were not changed around 100000 kms like they should be. i havent pulled one to see for sure yet but any other guesses of what it could be?

 

A vacuum leak, the PCV system is bad to "rot" out, esp. the elbows under the cowl. Check all those, and clean the IAC.

 

You may be due for plugs but you should also cean the throttle body when you do your IAC.