thanx for answering, i'm no mechanic so i had no idea u could do a self test, i'm goin to do that tomorrow after work, yes the check engine light has come on since i bought it, usually after i had been driving for 15 min, or went from a higher speed down to a low speed, it turns over still but wont fire, hasn't run for 3 days now, i'll get back to you again after i've done a self test, although i may not get to it as soon as i would like because i work full time, have a newborn, and i had the truck tower into town and i live out of town so i dont have direct access to it. thanx so much for the help this far sandie