Change oil light stays on even after oil change

You may need to reset it with a scanner.

Try re-setting the oil change light and see if it quits. Should re-set itself. Not oil sending unit, that tells computer and light when there is a problem like no oil pressure.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/michael_2496c4f07ad24453

TAKE THE TRUCK BACK TO PEPBOY AND TELL THEM TO RESET THE SERVICE INDICATOR

That could be from not having any oil pressure "oil pump failure, clogged filter, etc" or from a faulty oil pressure sending unit. More tests would need to be performed but is it really an oil pressure light or is it the change oil light. More info would be needed

Check your owner manual-- on how to reset the light or
ask a dealer to show you

To review, the check engine light will stay on until the problem is fixed and the code or codes are erased. And if the O2 sensor is disconnected the light will stay on for sure.
Do you have the trouble codes stored in the computer ?
FYI - the cylinders should have over 100psi of compression.

The change oil light needs to be reset after each oil change...some shops are not knowledgeable on how to do this...Your owners manual will instruct you how to reset the oil change light...The service engine soon is a catch all for low fluids and other needs...Be sure to check your oil level again...to clear the service engine soon light, you can disconnect either battery cable for 15 minutes then reconnect...if the service engine stays on...then you need to have your Grand Am checked...Auto Zone does a free diagnostic of check engine light codes...:)

have you tried changing the oil sending unit they can get bad also make sure wire to sending unit did not get pulled off

The oil pan has a sensor in it that need to be replaced. It screws in and you may lose some oil.

you most likely need to take the cat to a saturn dealership to have the code reset for the oil change light. Saturn is notorious for designing their cars so that it is necessary to the dealership for repairs.