Cadillac launched the Eldorado in 1953 as a two-door convertible; it was also the most expensive vehicle in General Motors' lineup. By 1998, Cadillac changed the Eldorado into a two-door sedan. A 275-horsepower, 4.6-liter V-8 engine powered the 1998 Eldorado. This Northstar V-8 engine required an oil change every 3,000 to 7,500 miles, depending on driving style and conditions. The 1998 Eldorado used GM's oil life system, which used data from multiple sensors to determine when an oil change was due and alerted the driver via a "Change Oil" message. You can reset this system through the driver's information center.
Sit in the driver's seat, insert the key in the ignition and turn it to the "Run" position, but don't start the engine.
Press the "Info" button on the driver's information center until "Oil Life Left" appears on the instrument cluster screen.
Press and hold the "Info Reset" button on the DIC until "100%" appears next to the "Oil Life Left" message.
Turn the key off and remove it from the ignition.
