Fuel vapors has nothing to do with engine temperature.
Get the engine block and pressure tested this will tell you something if there's leakage internally in the engine. Also pressure test the radiator cap.
If its still doing that-might be air lock in the cooling system get it bleed out.
Always bleed air from cooling system after replacing coolant. Set heater for maximum heat. Remove radiator cap. Loosen drain plug and remove drain bolt (if equipped) from engine block. Drain coolant reservoir. Fill coolant reservoir to MAX mark with 50/50 water-coolant mixture. Loosen bleed bolt and fill radiator up to base of filler neck. Close bleed bolt when coolant flows out without bubbles. Tighten bleed bolt. With radiator cap removed, start and operate engine to normal operating temperature. Add coolant if necessary and check for leaks
Saturday, September 29th, 2007 AT 12:54 PM