1997 GMC Jimmy Owner's Manual - Page 139

If the Light Is Flashing The following may prevent more serious damage t o your vehicle: Reducing vehicle speed. Avoiding hard accelerations. Avoiding steep uphill grades. If you are towing a trailer. reduce the anlount of cargo being hauled as soon as it is possible. If the light stops flashing and remains on steady. see "If the Light Is On Steady" following. 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 *justdrive through a deep puddle of water'! 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? I 1 so, be sure to fuel your vehicle with cpality fuel (see "Fuel" i n the Index). Poor fuel quality will cause your engine not to r11n as e,fficiently as designed. You may notice this as stalling after start-up, stalling whenyou put the vehicle i n t o gear, mistlring, hesitation on acceleration or stumbling on acceleration. (These conditions may go away once the engine is warmed up.) This will be detected by the system and cause the light to turn on. If you experience one or more of these conditions, change the fuel brand you use. It will require at least one full tank of the proper fuel t o turn the light off. If the light continues t.o flash, when it is safe to do so. s t o p the \?el?ic&~. a safe place to park your vehiclc. Find 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 the Light Is 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 s111-e fully install to the cap. The diagnostic system can cleter~nine the fuel if I f none of the above steps have made the light. turn off. have your dealer or qualified service center check the vehicle. Your dealer has the proper test equipment and diagnostic tools to fix any mechanical or electrical problcnls that may have developed.