Engine rattle noise with oil change light on - 1999 Oldsmobile Intrigue

Your oil level is low. Wait until the motor is cold and check your oil level. You could also check your level after a drive just shut the motor down and wait 20 minutes for the oil to seep back down out of the block. Pull the dipstick, whipe it clean and did it in again and see what your reading is. If it is between Min and Max towards the middle of both it is fine. If It is all the way up by Max you may have too much, but I bet your oil level is low, I bet when you check it, it will be down near the min mark. If thats the case, find out what type of oil your car uses and buy one quart of oil and add some of it to your motor. I recommend you add about a quarter of the bottle, then stop check the dip stick if still low add a little more. If the level is good then stop. It is critical not to add too much oil. When cars get older they tend to run hot and burn oil. My van does the same thing, I can change the oil and add 5 quarts and about 3 weeks to a month later I have to add a little more and I usually can hear when i need to add some oil because I get a rattle/ping and the idle just doesnt sound right, but once I add the little bit of oil everything is all good.