Hey there guys.. this site is amazing btw before i get started.
So I own a 1992 Eldorado etc w/ the 4.9l, ever since the day I got it, the coolant temperature fluxuates more than my weight Lol. One minute it will be pinned at 85 Celsius, next it will be going from 90-105 and then 5 minutes later will pin itself at 82-85 Celsius. i've replaced a couple of the old cooolant hoses going to and from the radiator, also replaced that cheap T near the firewall, and replaced my thermostat. Its the weirdest problem, mechanic at a local shop just said drive it and forget about the coolant gauge, but I dont want to have the engine blow up on me, so any ideas or help would be greatly appreciated. Let me know if I could give you more information. Thanks
Automobile(s): 1988 Allante' (sold), 1984 Eldorado, 84 Sedan DeVille
Re: Crazy Coolant Temperatures
First make sure no air in the system. Second, replace the radiator cap. If it is stable on the highway at say 85 to 90, but goes to 105 at a stop light, thats normal. The electric fans kick on at approx that temp. Do a search on this forum regarding purging air, burping the system.