You need the scan tool to scan for codes or scan CEL codes free at Autozone or Advance Auto.

Clean throttle body and see if it improves.

Edit. TB cleaning
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=920243&Forum=trouble&Words=p0401&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=allposts&Main=919728&Search=true#Post920243


"Always do the cheap and easy ones first." 1996 V6 ATX 96K miles