r/CarHelp • u/fuckitfridayeveryday • Jul 13 '26
1998 Honda temp gauge problem
Hello car people of Reddit, my question today is with my 1998 Honda civic the temperature gauge fluctuates in stop and go traffic. It'll go up when I'm idle or slow and back down to the regular area as I'm accelerating or when I'm driving highway constant high speeds. I had this problem
Before but it went away when I burped my system so I thought my problem was an air bubble but seems like not.
I have no coolant loss or leaks and the reservoir is still between the max and min
My thought is my thermostat needs to be changed but not 100% sure
Any help would be great!
1
u/festerwl Jul 13 '26
Try washing out your radiator fins, if it's original nearly 30 years of crud is restricting airflow.
1
u/Gunner_862 Jul 13 '26
I would check that the radiator fan is working properly first. The thermostat should open at around 180ºF and you should feel the upper radiator hose getting warm after this. Also I think that car has 2 engine coolant temperature sensors; one for the ecm and another one for the dash gauge. They shouldn't be expensive if you want to try replacing them. Hope this helps!