Cadillac Allante Forum Discussion, Overheats on the highway or at higher rpms for extened time in Past Cadillac Vehicle Discussion; I have a 1990 Allante. It runs good and shifts good but when I take it on the highway or ...
Automobile(s): 1990 Cadillac Allante and a Black 2005 Cadillac Escalade ESV
I have a 1990 Allante. It runs good and shifts good but when I take it on the highway or on really hot days if I am holding a higher rpm it overheats. Under normal 40MPH roads it doesn't get above the middle bar. I have checked the fans with the DIC and they both work. The coolant level is good. I'm not sure where to start, with the fan speed or the water pump? Any help would be great!
Automobile(s): 1988 Allante' (sold), 1984 Eldorado, 84 Sedan DeVille
Re: Overheats on the highway or at higher rpms for extened time
First things to do are replace radiator cap with a DELCO brand one, then Burp the system to rule out trapped air in the system. THEN, take it to a radiator shop that has an infra red thermometer. They will test sections of the radiator for cooler areas. Cooler areas are blocked areas.