1994 Buick LeSabre Owner's Manual - Page 115

Malfunction Indicator Lamp (Service Engine Soon Light) If it does not come on at all, have it fixed right away. If it stays on, or it comes on while you are driving,the computer is indicating that you have a problem. You should take your vehicle in for service soon. SERVICE ENGINE SOON SERVICE ENGINE SOON 1 NOTICE: If you keep driving your vehicle with this light on, after a while the emission controls won't work as well, your fuel economy won't as good and be your engine may not run as smoothly. This could lead to costly repairs not covered by your warranty. A computer monitors operation of your fuel, ignition and emission control systems. Thislight should come on when the ignition is on, but the engine is not running, as a check to show you it is working. 113