1998 GMC Safari Owner's Manual - Page 148

If so, be sure tofuel your vehicle with quality (see fuel "Fuel" in the Index). Poor fuel quality will cause your engine not to run as efficiently as designed. may You notice this as stalling after start-up, stalling when you put the vehicle into gear, misfiring, hesitation on acceleration or stumbling on acceleration. (These conditions maygo away once the engine is warmed up.) This will be detected by the system and cause the light to turn on. Oil Pressure Gage The oil pressure gage shows the engine oil pressure in psi (pounds per square inch) when the engine is running. If you experience or more of these conditions, one change the fuel brand you use. It will require at least one full tank of the proper to turn the light fuel off. If 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 any mechanical or electrical fix problems that may have developed. Canadian vehicles indicate pressure in a (kilopascals). P Oil pressure may vary engine speed, outside with temperature andoil viscosity, but readings above the, low pressure zone indicate the normal operating range. A reading in the low pressure zone may be caused by a dangerously low oil level other problems causing low or oil pressure. 2-64