Do I need to check the timing if I just changed the spark plugs on my 98 chevy cavalier?

yes because i had a 97 cavalier which i had the same problem so then the tranny went 4 months after the timing was replaced and it was $500 dollars for a new tranny so i sold the car for $300 dollars

You need a timing light...after that you'll need a golf tee to plug the vacuum advance with and to put a paperclip between to points on the diagnostic plug, chalk mark TDC and twist the distributor until the timing mark comes to 7degrees TDC...thats a start~

some sparkplugs are defective, try to put the old one, if its more ok, buy a new one( platinum)

Would assume it is the 2.2 not the Twin Cam. This is a DIS Judge Roy e-advance. Did you reconnect the spark plug wires the same way they were before you cahnged the plugs? From pass to drivers Cly #'s 1-4 and wired on the DIS coils 4 and 1 then 3 and 2.

drat.~

http://autorepair.about.com/library/firing_orders/bl-fo-4432.htm