Overheating in town, not on highway **problem fixed**
 

ok, I was having overheating problems on the highway two weeks ago and it ended up being my radiator, it's been running fine since I put a new one in but now it's overheating in town, anything below 45mph the temp just goes up fast, but over 45mph it runs at normal temp. I wasn't hearing the fan kick on, so I jerry rigged some wires up so i could just turn it on manually in the interior, but even that didn't keep the temp down, but if I turn my heat on full balst , it will keep the temp at normal. :-\ O, one more thing ,it did start to rise in temp once or twice on the highway when I was going up a hill, but when I turned the heat on, it dropped back down.

Re:Overheating in town, not on highway
 

just found out my fan does turn on, so I know it's not the sensor, well...it might be GOING bad, hum...

Re:Overheating in town, not on highway
 

Using coolant or water?
Maybe bubbles in the coolant system...
Or Flush the coolant system.

Re:Overheating in town, not on highway
 

I just flushed the coolant a week ago, for sure no bubble, and i'm using water/coolant, and I just put some additive to the coolant to lower the temp, still didn't fix it.
I drove it for like 40 mins in town and a little on the highway and it started getting a little hot, not over heating after like 45-50 mins. do you tihnk it could be a water pump or thermostat? I checked my lines and the feel full.???I hate problems like this

Re:Overheating in town, not on highway
 

get a alum core radiator... my engine has never gotten hot with it. and it takes a long time to start overheating sittin in traffic without the fan on (i use a switch fan)

my rad was 135 on ebay, funny thing is that fan was 119 at car quest >:(

https://www.homemadeturbo.com/jbliss/fan.jpg

Re:Overheating in town, not on highway
 

hmm; $119 for that rad? did it come with that fan?
my rad in my 90 civic si has seen better days and i need a slim fan. Looks like i may have just found a new cooling system :)

Re:Overheating in town, not on highway
 

sounds like the thermostat could be a good possibility. if it's not opening properly, you could be getting very little coolant flow through the radiator. if i'm not mistaken, the radiator fan thermo-switch is in the coolant flow returning from the radiator on 5th gen civics. in that case, the radiator fan wouldn't turn on because the coolant returning from the radiator would be nice and cool, it's the overall coolant flow that's being choked by the thermostat.

Re:Overheating in town, not on highway
 

my rad was 135 on ebay, funny thing is that fan was 119 at car quest >:(

Re:Overheating in town, not on highway
 

I'm going to change the thermostat tonight, mainly because it's the cheapest ix, if that doesn't do it, I'll do the water pump. Is there some kind of compresion test I can do to see if the heaad gasket is going?

Re:Overheating in town, not on highway
 

what the heck, I took it out today and now I can't get it to overheat...not that that is a bad thing, but i'm going on a 950 mile trip next week!! and I want to get this thing solved. I have noticed that when I take off my radiator cap, that there is a ton of pressure under it that it lets out, a lot.