Honda Civic Is Overheating

Posted in Internal Engine Parts
  • Ok im at a loss here I have a 98 Honda Civic and its overheating. The fan tests ok and so does the fan relay. It has a new radiatior, radiator cap, thermostat, coolant sender gauage. Water pump is not leaking. The thermostat is opening b/c the top hose gets hot. Also the fan works however it never kicks on while it overheats so I rigged it to stay on at all times yet the car still overheats. Must be internal. Any suggestions?

    There are 4 Answers for "Honda Civic Is Overheating"

    1. Djdontriel says:

      Yes . you should probebly take it and get it tested at your local firestone or a place or ur best convience to see if you passibly have a cracked head or head gasket. if your coolant system is up to day as you say, that would definantly be yur next option. do this, go chech your dipstick. if there is water mixed with your oil that is definantly the problem.

    2. Vtec1707 says:

      Thermostatic Switch faulty, Ignition timing incorrect, or ignition fault, Airlock in cooling system. Also, is the grille restricted? You should flush out the radiator also.

    3. Honda Guy says:

      Could use more information on WHEN it is overheating…does it doe it all the time or only under certain conditions? is it time relavent (after say 15 minutes of driving under any conditions) or is it conditional (only in stop and go traffic, only at highway speed, only on uphills, only on hot days? the more information the better the chances of helping you.

      as for what you supplied so far–the radiator fan is triggered by a thermo switch that looks like a coolant temp sensor. it is uaullaly on the passenger side of the engine either on the water outlet or near there. that is the ‘signal’ for the fan to turn on when the engine temp is above the set threshold.

      beyond what you’ve done, there are the possibilities that you have air in the system that would cause the temp to fluctuate up and down. you need to bleed the air out when you replace a radiator by filling the system with the top of the radiator above the top of the heater core. most techs use an adaptor for the radiator cap that holds a large funnel to accomplish this. if you don’t have that, you can remove the coolant overflow jug and hang it from the hood so that the jug is avbove the ilevel of the instrument panel. then fill the jug 3/4 way and run the engine. when the thermostat opens the level in the jug will drop to replace the air in the system.

      another possibility is that you have a blown head gasket. can’t overrule that possibility. you may not be blowing white smoke but you could be pushing exhaust gases into the coolant. you need to do a compression test to check that and a block test to check for the pressence of HC in the coolant to eliminate that possibility.

      also, if the temp is fluctuating, check the coolant mixture. if the mixture is all coolant it is extremely unstable and will cause the temp to fluctuate wildly. coolant is at its strongest in a 50/50 mix with coolant and water.

      again, the more you can tell us about when and where the better the chances of narrowing down the possibilities.

      hope that helps

    4. Mikaela P says:

      If everythings you’ve mentioned are all okay, check your radiator or reservoir for some sign of oil mix. If there is, a possible blown cylinder head gaskets causes your overheat. Have it replace at once because this is very dangerous, if it reaches the block and piston.Hope this helps!