1998 GMC Safari Owner's Manual - Page 147

If the LightIs Flashing The followingmay prevent more serious damage to your vehicle: e Reducing vehicle speed. e Avoiding hard accelerations. e Avoiding steep uphill grades. e If you are towing a trailer, reduce the amount of If the LightIs On Steady You may be able to correct the emission system malfunction by considering the following: Did you recently put into your vehicle? fuel cargo being hauled as soon it is possible. as If the lightstops flashing and remains on steady, see "If the LightIs On Steady" following. If the light continues to flash, when it issafe todo so, stop the vehicle. Find a safe placeto park your vehicle. Turn the keyoff, wait at least 10 seconds and restart the engine. If the light remains on steady, see the Light "If Is On Steady" following. If the light still flashing, is follow the previous steps, and drive the vehicle to your dealer or qualified servicecenter for service. If so, reinstall thefuel cap, making sure to fully install the cap. The diagnostic system can determinethe fuel if cap has been left off or improperly installed.A loose or missing fuel cap will allow fuel to evaporate into the atmosphere. A few driving trips with the cap properly installed should turn the light off. Did you just drive through a deep puddle of water? If so, your electrical system may be wet. The condition will usually be corrected when theelectrical system dries out.A few driving trips should the light off. turn Have you recently changed brands fuel? of 2-63