Rep Power: 0

Hi everyone,

I have 2006 civic EX, it wouldn't heat up when I let it warm up. The temp gauge would not move unless I drove it, then it wouldn't go past half on temp gauge.
The upper rad hose would get warm, the bottom would be cold. So I replaced the thermostat based on reading other threads.
Same issue. I can let in run in my heated garage for 30 minutes, gauge will get to half, upper hose warm, lower cold, and the rad fan will not turn on.

It blows warm after the gauge gets to half

looking for help as it's my kids civic and she needs this car

Thanks

 
Rep Power: 125

Honda’s are notorious for not cooperating with aftermarket sensors. Did you buy an OEM one?

Assuming the thermostat is okay, the coolant level is fine and there are no leaks, it could be a heater core.

 
Rep Power: 0

I put in a aftermarket thermostat.

 
Rep Power: 125

I won’t guarantee that’s the problem, but it’s probable. Some people have had luck with them, but they fail more often than not.

 
Rep Power: 367

2006 is a 8th gen car, engine is very different.
Moving to proper section

 
Rep Power: 223

Everything you said sounds fairly normal. It's just a little 1.8L, it's going to take some time to warm up especially if it's cold out. The lower rad staying cold isn't a concern unless the engine is overheating.

 
Rep Power: 99

I have a 7th gen so it may be a bit different, but my car acts the same way yours does and my cooling system is working great. These are small engines, so it's going to take some time to get up to temperature. The temp gauge should be at half at normal operating temp...that's normal. If idling only (even in a heated garage), it will probably take a LONG time for the cooling fan to come on. You'd have to drive for a while and then let it sit and idle.

Also, I RARELY see my temp gauge go past half except when idling in hot weather. The cooling fan kicks in only slightly after half on the gauge reading.

Do you have the heater fan blowing while you're warming it up? That will affect the time it takes the engine to warm up depending on the fan setting. If the fan setting is on high or even medium, the engine may never get hot while idling.