Monday, September 27th, 2010 AT 9:17 PM
My 1993 mercedas 300E 2.8 was doining fine two weeks ago. Now Ive notice the temp. Guage creeping close to 120C. I checked coolant it, s ok. I locked the fan clutch still no change. The aux. Fans comes on about 100C. I changed the oil still no change. Replaced tank cap. When temp. Gets close to 120C I turn the heater on the temperature drops to almost normal, I cut the heater off temp. Start to rise again. When vehicle is at idle temp. Stays close to normal. Do you think it could be an air lock in the system?. HELP

