Ok, I've searched and searched and can't seem to find this anywhere... Should both radiator fans run all the time, or just 1 then the other come on when the a/c is on? I have 1 that runs and 1 that doesn't, but I haven't done any diagnosis on it yet, anyone know if they should both be on? Thanks!

 

Radiator fan should not run all the time. It runs only when temperature is over 95 degree, I think. If it runs all the time, you probably want to check the fan switch. The other fan is for AC, and should not run all the time neither.

 

the passenger side should be ac controlled and might come on as a secondary cooling unit too, not sure
the driver side fan is the radiator temp controlled one and should come on and off as needed, it should not run for an hour after shut off- that would be a problem

 

Like said above. Only 1 typically runs. The other one is for the AC

 

Ya I just changed out my condensor fan due to its burning out


IF the condensor fan wont go on or even the radiator fan for that matter either, then you have a problem. But usually the condensor fan comes on when AC is turned on.


OH and tell tale signs? fan running when car is off, and a lake of coolant under your car when you stop. trust me, ive been there

 

Ok, sorry I didn't mean "all the time". I was refering to the driver's side fan and whether it is coolant temp dependent or just controlled by the a/c compressor being on or not. I think I'm understanding it to be solely controlled by the a/c system. Is this correct?

 

The driver side fan is controlled by the radiator fan switch. The passenger fan is controlled by the AC.

 

Ah, ok thanks for clearing that up guys. I'll give it a closer look and see what's going on, there.

 

so here's my situation:

I took my car to the acura dealer to get the cooling system checked up as i was getting overheating. Prior to this i read through several forum posts about a fan temperature sensor that seemed like it could be my problem, but after trying to buy the part at a local auto parts store, there seemed to be so many sensors etc i didnt want to get the wrong part. So i finally took the car into the dealer to get checked out.

they diagnose the problem as the radiator fan needing replacement ( i specifically told them i thought it was one of the sensors but i doubt they checked up on it once they saw the fan was out).

I decide not to get the work done at the dealer and do it myself. With new fan installed i thought my problem was solved. No. today driving home in 100 degree weather in traffic, car began to overheat once again. After getting home and parking the radiator fan remained on for close to 18 min after car shut off. when i initially shut off the car the temp might have been half way up the meter, after shut off and maybe a few min i turn my key to the on position to check the temp guage, its now 3/4 up the meter!

Is that normal for the engine to read as it heats up AFTER its shut off? could my problem still be a temp sensor? thermostat maybe? please help!

 

What exactly do you mean it was overheating before you went to the dealer?
how much past halfway was it and how many times did it do that

how is the fluid level in the res bottle and the radiator now?
Is there a fluid leak, based on those fluid levels?
Usually its the fan temp sensor causes fan running on

Its located at the lower corner rear passenger side of radiator or at the thermostat-depending on year

the dealer tech checks for power to the fan motor and supplies seperate power to the motor to test it, then after new parts are installed they run the engine till fan comes on then turn engine off- listen for fan to come on for a minute or 2 then off
At least they are supposed to

If you had a longterm overheating which caused the fan to operate more than normal and wore it out--it also may have caused other engine damage

How is the oil level- suddenly above the full mark? brown-foamy?
and the radiator fluid- green or now has oily surface?

It could be a thermostat problem or water pump- whats your current mileage and year car

 

i have a 2000 tl with almost 152K miles. before i went to the dealer the car would overheat only when i had the AC running in hot temperatures in highway traffic or inner city driving. I noticed that the fan would run a long time after i shut the engine off also that's why initially i suspected it was a temp sensor.

I havent checked the fluid levels in the radiator and res since i topped them off when i noticed the over heating.

I havent checked the oil recently, but it sounds like i should check it right after shutoff to check for brown foamyness? what would that indicate? wat does an oily surface in the radiator fluid an indication of?

The car will never overheat unless the AC is running and its hot outside, so if a water pump was out wouldnt it just overheat with normal operation?

also what could be up with the meter reading half way up at shut off, and after shut off suddenly increase in temp to 3/4 up meter?

 

Brown foamy oil/oily radiator fluid = head gasket leak & possibly warped heads.

 

If there's coolant in your oil, you have a bum head gasket. I would check to make sure your thermostat armature didnt freeze up. That happened to a buddy of mine on his civic. No coolant was getting into the engine. People commonly misdiagnose a bad thermo as a failed water pump. Squeeze the lower radiator hose while the car is on and warm. It should have pressure in it. If not, it might be time to raplace that thermostat, and then move on to the more costly stuff.

 

was the water pump replaced at 105? or since then?
If never replaced thats is most likely suspect in long term running hot.. runs hotter with ac
or runs hotter on hills
AC does put extra demand on the engine, its radiator sits in front of the engine radiator- throwing more hot air at it when ac is working

Does the passenger side fan run with ac on- it should
driver side fan should come on with temp and sometimes ac iirc

the fact it been running past half- 2 ticks below half is normal, I would check the coolant levels and the oil immedialty to see if its a major problem or a replace water pump or thermostat job

Yes its normal for the temp to rise ~slightly~ at shutdown,,3/4 seems high but I never watched for long ..my fan runs- turns off- Im satisfied

When you shut the engine off, the water pump is no longer turning to expel hot water from the block, plus the location of that temp sendor- cause the guage and real temp to go up - thats why the driver side fan comes on for a minute after shutdown- to help blow away heat so the fluid inside it doesnt get a big spike in temp

If its gotten low enough on coolant to get an air bubble inside, that will get behind the thermostat and fool it--owner book has method for refilling coolant and burping