Jeff Mizner

I'm having temperature issues with my 99 Honda Civic Ex. I've linked a video on exactly what's going on. It starts overheating at idle. If I push accelerator, temperature decreases. If I keep pedal at about 1500 while parked, no issues at all (temperature remains constant at about half way up). Here's the video.
https://youtu.be/FS83ACWxPNQ

mk378

Is the cooling system full?

Park on level ground or facing uphill. Wait until the engine is completely cold. Take the radiator cap off and check in the radiator. Do not just check the white plastic tank. The radiator must be full to the top. And the white plastic tank should be about 1/3 full.

Jeff Mizner

Thank you for your response. Yes, the reservoir is filled correctly. Radiator is full. I keep thinking it's a bad thermostat.

Cluek24

How's it going bro ? Well I had an issue happen like that ones on my civic but my problem was the heater core . It was winter and I was driving with my heater on and I heard a gurgling sound coming from my lower passenger dash I was like damn ....i was think it was a air pocket so I worked on it and everything sent good thermostat opened 2x so I was happy o drove for a while and I turned on the heater again and a few minutes down the road there it was again😏I was like damn Daniel we have have bad heater core so what I did was just leave my hear level to cold and until I fixed it but how hot is your bottom radiator hose?

Jeff Mizner

I don't know how hot the bottom hose gets. I'll run it tomorrow and tell you. I live in So-Cal, so I rarely use the heat. Most of the time it's either AC or windows down. I had an issue with the hose that went to the heater core last summer (the hose that connects to the engine right below the dizzy). The hose had hardened and cracked at the clamp. I replaced it and haven't had any issues since. This issue is fairly recent (about 2-3 months).

some one

from my experince if the car dont overheat while in idle and only when pressing the gas pedal its a blown gasket .
there will be no smoke ,just overheating .
its something to do with the open deck engine design .

But befor you rush to change the gasket you should check if there is water pressure , when the car is cold remove the upper radidor hose then start the car in a few mintues there should be water comming out , dont forget to keep topping up the radiditor , if there is no water comming out , remove the thermostat and reapeat the test , if there is water comming out its a bad thermostat . if not there is either a jam in the system or a bad water pump , if water is comming out and the car still over heat its a bad gasket.

i prefer not to use the steel head gasket if you can find it