I hope someone can help me out.......i just got a 93 civic ex coupe last week and it was running fine until a few days ago i noticed when i am on the highway(speeds of 65+).....my engine temp goes up, but as soon as i get off the highway and do some city driving the temp drops back down.......i am driving with my defrost on full blast when i am on the highway and it keeps the engine cool enough for highway driving, but its june and its hot........why would my car only overheat on the highway?.........also, i flushed the radiator out but it didnt help
anyone ever have this problem?....thanks

 

anyone?

 

is your radiator fan cycling on and off?

 

yes, radiator fan is cycling on and off just fine.......i think i am going to replace the thermostat and flush and fill and bleed the cooling system.....hopefully that works

 

Maybe your thermostat is getting stuck?

 

Did you do a coolant flush recently? Maybe there's air in the radiator? Take off carp, run engine for 20min with heat on full blast, see if any air bubbles come out. Just a though. More likely thermostat though.