So I went on a little trip that lasted 3 weeks. At that time the Ranger was sitting under my car port. The day I got back did the usual inspection but didnt find anything uncommon. The first day the truck drove good. After a few days it began to have this rough idle but without any drop in the rpms.

It will idle normally and like about every 5 seconds or so it would feel like the rpms drop but come right back up. Let me just say the truck works good when cold but once it warms up it starts doing it. After 40mph the truck starts hesistating. I have to almost floor it to reach a steady 50 mph in the slow lane. Once there the stutterting and jerking stop. Once I slow back down to 40 or so it does at again. At times the a/c would stop cooling but then would blow cold again after a bit????????

The check engine light just came on yesterday so i am going to have it checked out. Does any of the symptoms sound familiar? I hope it just needs a basic tune up.

03 4.0 sohc with 146k