Well, about this same time last year my radiator fan started running for a couple minutes after the car was shut off, then progressively ran longer and longer after shutdown, maxing at about 15 minutes. Then the temp needle began to move while driving and the car began to run hot. (time line of these events was about 2 or 3 weeks. Bought a coolant temp sensor and got the radiator vacuum flushed. Before having to install temp sensor, the car ran normal and never had another issue after the flush... Until now. Exact same thing is happening again... The running hot issue is perplexing... the car runs fine for 15 mins then the needle moves a little above half, then back down, then to 3/4 then to normal, then to H, then back... its all over the place. Stop lights: it will be okay, then if 30 seconds passes, screams to the H. Soon as you start to move it goes back down. Almost like airflow cools it down again. I changed the temp sensor this morning, no difference. Coolant overflow/reservoir is full to the top. Now im thinking the other temp sensor/cooling fan switch located on the thermostat housing is my next move and possibly a new rad cap.

Any thoughts? never replaced a single cooling component on this car for the 50,000 miles ive owned it. Radiator says Honda so im assuming its original...

 

ck rad cap for cracks or general worn out- parts store can pressure test
Vac cleaned rad? huh?

coolant res bottle should be about halfway, has cold and hot marks..
never full- that can indicate pressure from inside engine
Pour out/turkey baster suck out excess so you can monitor the level daily

next would be thermostat- the way its getting different temps- could be sticking

whats the cars mileage- done the water pump/105 service yet?
hows the oil look and smell, no brown foamy too it- level suddenly up or down above normal?
same with coolant in rad- any oily transfer or brown ick- signs of bad news from head gasket
the TL does not like to be over half on the guage

 

as far as I know,,, there is only one driver fan temp sensor- located at bottem of rad passenger side (00 and later)

not sure whats on the thermostat cover,,(99s is the fan sensor)
the dash temp guage sensor would be likely,

get a thermometer and run car with rad cap off to ck actual temps

 

coolant reservoir was definitely full to the max, the coolant at the top didnt look great, but the coolant at the bottom was good and green... havent checked the oil condition would it be noticeable on the dipstick? and i work at a local auto parts store, everyone i talked to said it may be the water pump? its not leaking but yeah the service was done i think at 90k... maybe 100k. mileage now is 150k...

 

ck the hose inside res cap - that likes to fall off and transfer system wont work

wp is possible- do you know if acura or other was used? aftermarket 60kmiles--very possible!!
ckd for anything from the weep hole?
Its a bit of labor to do, so not something you change on a guess

the high level in res bothers me,,please remove the excess so you can properly monitor that level- it tells a lot if things!-
the whole bottle pulls out and you can dump it- put some fresh 50/50 mix in

oil getting coolant mixed in will show on the dipstick as change/rise in level, and color of oil
ck in rad for same

 

do you know as fact the wp and tbelt were done at 90? saw the paper for it?

 

saw the receipt and online on myacura...
heres what my coolant looks like :/

not running the car anymore until i begin to fix something going to start with the thermostat...

 

yikes! from the bottle or the or the rad itself?

drain out all the coolant- from engine block drain too
thats got zero cooling abilty!

 

Thats from the bottle. getting a stat today may change tonight...
color doesnt look good, but doesnt look like oil mix to me

 

lazy tech didnt change the bottle contents with the 105 service

if there is oil it will seprate and show up well in your container
still -watch the dipstick

 

yeah everything seems to be where its supposed to be (oil with oil coolant with coolant) but my next job is to change that thermostat... just looking at it, it seems not too hard to do... ever done it?

 

Arent our cars supposed to have a blue 50/50 coolant in them also?

 

there are some who swear by acura coolant
and the rest of us use one thats ~approved for acura~

get a real acura thermo and gasket
ck the direction on install--see diy
I know it has some indicator, that if installed wrong causes probs

 

Well, i took my radiator cap off today for the 50th time and noticed it looked odd... looked down into the coolant port, and found a little tiny plastic piece in there. removed that and realized it was part of the cap! so now im thinking just replacing the cap and getting pressure back and hoping this will be the answer! still trying to track down the right coolant...any brands off the top of your head? i dont really want to throw prestone universal in there unless i know its kosher...

 

read back of bottle- it will say APPROVED for acura if its the right stuff
most of them are now--
whatever ingredient caused a prob seems to have been removed
except a brand for cars needing that specific thing

 

didnt I mention the rad cap a while back???? post 2 iirc

very ccommon to need a rad cap after all these years
they are cheap and may improve your overall cooling for the summer

 

Replaced my cap and everything seems to check out now. Fan still cuts on for a while every now and again... not real sure. it is close to 100 around here during the day..

 

the driver side fan should run for ~1 minute when you are sitting stopped, then say 4 minutes off and run for a minute--senses slight temp change and acticates to pull heat from the radiator

Once moving it may run occassional and with ac operation

 

It runs with the car off, for about ten mins occasionally...

 

guess what you need! a fan temp sensor

 

is that the one on the bottom passenger corner of the radiator?

 

yes it is--mentioned in nearly every post on temp probs--if fan op funny- replace sensor on pass lower corner of rad
It screws in