Alrite so i have a 97 civic ex . On tuesday morning sitting in traffic for school my car began to heat up so i turned off the air conditioning and the guage started goin up slower and once I began to move the guage went back down, but then when i turned the ar conditioning back on the guage began to go back up until i got to around 50 or 60 and then it went back down. After class on the way to work i experienced the same issue, it would go up until i hit about 50 and then it would go down. I had this same problem about a month ago and i first replaced the thermostat and i still got the same problem. Then about a week later it stopped doing that. Now its starting again but this time i noticed that the cooling fan was not turning on when it was supposed to. Now for my next problem is that it works fine at the moment, since tuesday ive sat in traffic with no problems, the fan turning on and everything. Im wondering what could cause the fan to work correctly on some days and not correctly on others. What should I start with?

 

Probably the fan switch, which is next to the thermostat. It could also be that your fan motor isabout to completely wearout, but that's going to get worse fairly rapidly.

Carry a piece of wire with you to jump the switch next time it happens, if that gets it started then replace the switch. Or if you feel like gambling $30 on a fairly safe bet, just replace the switch now.

 

the guy at advance showed me a radiator fan switch and a coolant temp. sensor. would it be safe to get them both?

and when is the fan switch located? is that the plug right where the thermostat is located?

 

It's the one on the thermostat housing. The other sensor is not involved in this problem, you don't need it.

 

my haynes manuel says that the one that goes into the thermostat housing is called a ECT sensor?

 

i also read that it may help to have my radiator flushed. is that right?
also i attempted to get a cooling fan relay and was told at every store that they couldent even order it.

 

The radiator is not too bad because it does stay cool on the highway. I looked at the Advance website and I'm not sure they have the switch, just the sensor. The relay may have to come from a dealer but most people here who have had fan problems report that it was the switch.

 

ok so i replaced the radiator fan switch aand the coolant temp sensor. Then i decided to drive to Jiffy Lube and had the syestem flushed. At the light rite next to Jiffy Lube the temp guage began to go up, then i pulled into the parking lot, opened the hood and saw the fan running, then looked back at the guage and it had gone back down. I had the system flushed and the rest of the night experienced no problems. Hopefully that was the key.
Also I am just wondering, i got sort of confused. Which one was the sensor? one was in the thermostat housing and the other was sortof underneath the distributor.
And do you know how much the relay may cost? Ill call in the morning but i thought you may know a range

 

alrite so the problem is back, ive replaced the thermostat, the temp. sender, the cooling fan switch and the collant. Today im going to the dealership and geting the relay. Any other suggestions?

 

If the fan is turning on when the engine is overheating, the entire fan circuit is fine and you should look elsewhere for your problem. You can test a relay, its not even that hard. The relay has a coil side and a switch side. Hook up the coil side to power and ground and check the resistance at the switch side. If the resistance is low, then the relay is working fine. Also, when your engine begins to overheat, turn the heat on (turn the A/C off) and turn the fan to high. Your cabin will get hot, but this will remove heat from the cooling system.