1998 Chevrolet Astro Owner's Manual - Page 147

If the Light Flashing Is The following may prevent more serious damage to your vehicle: 0 0 If the LightIs On Steady You may be able to correct the emission system malfunction by considering the following: Did you recently put fuel into your vehicle? If so, reinstall the fuel cap, making sure to fully install the cap. The diagnostic system can determine if the fuel cap has been left offor 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 lightoff. Did you just drive through a deep puddle of water? Reducing vehicle speed. Avoidinghardaccelerations. Avoiding steep uphill grades. If you are towing a trailer, reduce the amount of cargo being hauled as soon as it is possible. 0 If the light stops flashing and remains on steady, see "If the Light Is On Steady" following. If the light continues to flash, when it is safe to do so, stop the vehicle. Find a safe place to park your vehicle. Turn the key off, wait at least 10 seconds and restart the engine. If the light remains on steady, see "If the Light Is On Steady" following. If the light is still flashing, follow the previous steps, and drive the vehicle to your dealer or qualified service center for service. If so, your electrical system may be wet.The condition will usually be corrected when the electrical system dries out. A few driving trips should turn the light off. Have you recently changed brands of fuel? 2-63