Place oil in a multi-functional pressure cooker (such as Instant Pot) and select Saute function. Add beef, onions, celery, bell pepper, and garlic. Cook and stir until beef is browned and crumbly, 5 to 7 minutes.
Add water, spaghetti sauce, rigatoni, Worcestershire sauce, thyme, salt, and pepper; stir to combine. Select high pressure according to manufacturer's instructions; set timer for 4 minutes. Allow 10 to 15 minutes for pressure to build.
Release pressure carefully using the quick-release method according to manufacturer's instructions, about 5 minutes. Unlock and remove the lid.