I recently replace most of my cooling system Rad, upper/lower radiator hose, thermostat, coolant, and radiator cap.

everything was working fine until i ran into a problem with air in the system,
that was an easy fix by burping the car.

Then i had everything work for about a month now i find that there is a problem with the fans.

I searched about the fans and found alot of people with the same overheating problem but no one really said how to solve the fan issue. My fans while driving does not turn on only when i turn the car off. which causes the temp to rise at a stop and fall back down to normal when driving. It bounces from mid range to high and fluctuates like that back and forth. I am getting sick of this cooling problem and its not even hot outside. And i dont want to risk a BHG =x

Please help with any info so i can get this done with i greatly appreciate it

 

lower right -passenger side - corner of the radiator is a temp sensor for the fan- or depending on year- its next to the thermostat housing
If the fan runs a long time after shutdown that s a likely suspect
The driver side fan is temp controlled by semsors- the pasenger side fan is controlled by the AC- turn ac on- fan comes on to add airflow thru its system

Make sure you got a genuine Honda thermostat
The temp should not be going up and down like that anyway- check the small hoses for the system- if soft they collapse under pressure and stop flow
the owner manual has the coorect procedure for burping the system- takes about 20 minutes in the driveway to get it all done perfect acuras way
If you fail to open the heater core- thats a problem !

 

how's the water pump?- how many miles on it
if you had to replace the radiator I am guessing it looked pretty bad inside-

 

check all the hose clamps too- you never know what small thing causes other problem

 

I replaced it with a genuine honda thermo from the acura dealer , car was burped correctly. Car a 99 and has 173,000 on it and i will check the hose clamps tomorrow morning.

Also the fans do run a long time after shutdown

 

i will try and replace that sensor tomorrow most likely

thanks for the help
i will get back to you with the results

 

If you fail to open the heater core- thats a problem !

i was wondering what you meant by that ?

 

when you burp the system the heater must be on HOT HIGH- its control valve Open- so that it gets drained and refilled with fresh coolant.
The heater is a mini radiator that coolant does flow thru.
It can hold a large air bubble if it was closed at refill time.
Then you turn it on and get an air bubble introduced and that causes big problems

 

WOW! dang i must of missed that....

what kind of problems can occur and if i re burp the car will it work again?

 

just read your owner manual for the complete instructions for your year and do it per them-- exactly

My 01 was something like turn heater to hot- fill rad with new mix, start car, fill rad as needed- then idle with cap on but not tight- until fan came on- then refill- then continue idle until fan runs 5 minutes- then refill- then yadyada

here is the free owner book in case your is buried in the house
click year then model- move hand over index, click to open and pick what you need.
can read or print or donwnload sections or the whole thing if you want
https://techinfo.honda.com/rjanisis/...01_OMANUAL.asp

 

well after asking my mechanic he said it is the temp cooling sensor which is needs to replaced in order for the fans to work. I will try and get one tomorrow from acura to replace and see what is up from there.

I will keep u posted on any updates with the car

if i keep driving when it heats up and the temp goes back to normal is that still ok for the next week? cuz i will be busy, but i want this fixed asap so far temp is ok only when i go up a hill or drive with my heavy foot it happens but as the car moves the temp goes back to normal + turning the heat on full blast for a bit not even a minute

 

FIX IT NOW!!!
Each time the guage goes above 1/2 you are in the danger zone of damage to the head gasket,,, which may not appear for 6 months-

Opening the heater to add that extra amount of cold coolant is an emergency trick ONLY!
NOT a get me to another week while I take a trip. As soon as you open it it takes in hot water and pushes its stored coolant into the system.- Dont have to leave it open- that just makes the cabin temp increase

The driver side fan is temp controlled by the sensor while the passenger side comes on with the AC control to pull air thru the ac radiator- its in front of the engine radiator

the fan temp sensor goes in the lower passenger side corner of the radiator or next to the thermostat depending on year
Should be a fast install if you can drop the car off the night before- so its cold to work on first thing in the morning

Print out the owner book instructions on burping and give to the tech
all cars are different- cant expect someone to remember each ones specifics
and the TL is picky picky
Is the coolanbt you used 50/50 premix- or you mixed? and was it from honda dealer or say `Approved for Acura` on the label- specifically?

 

This is definitely something to take care of now. You do not want the engine overheating regularly like that- could get very expensive. Drive something else until you get it fixed.

 

I am having the same issue w/ my '99. I just got a new thermostat/hoses/and fluid from the Honda dealership and plan to replace it all this weekend. for now I try to not drive. Hopefully it is just the thermostat because the car will start to get hot real quick while sitting with the A/C on (106 yesterday in Dallas so it was on for sure!). It seems to not get as hot as quick with the A/C off, and it returns to normal when driving over 40 mph.

I also noticed when I got home that the driver's side fan was NOT on while the passenger side was running. They do not run after the car is turned off. I thought the driver's side fan should be running really all the time when the car is sitting?

 

yes it is suppose to run, got my mechanic to take a look into my car and he said its the coolant temp sensor A but also if i remember correctly he also said there is a temp sensor B on the car we will be fixing the problem as of sat hopefully thanks for all the info and i have not been driving my car well only to school the the problem does not happen.....but if i drive more than 10 miles yes it does occur but car is sitting at home right now i plan to also to flush my system and replace with coolant once more

 

ou sig
Please read the owner manual for details- your year may vary, so read the book

The TL should never go over 1/2 on the temp guage- usually 1-2 ticks BELOW half, even at 110 degrees doing 80 mph and a very steep hill with the AC blasting--
Thats just going to reno-tahoe on a typical summer day- and up to 7000 feet too!

The driver side fan is temp sensor controlled- for the engine temp, and may run a FEW minutes after shutdown.
It will run `on and off as needed` when stopped at idle or in traffic-- when airflow thru the radiator needs to be artificially increased

Part of the burping procedure in the book calls for waiting for the fan to come on and off- then on and run a certain amount of time at 2000 rpm- then......and....

The passenger side fan is automatically on with the AC ON- Its purpose is top pull air thru the AC systems radiator (condensor) it sits in front of the engine radiator
It should have a backup sensor to aid the driver side fan in extreme emergency- havnt tested that for myself!!! maybe thats the B sensor

If you are going to change the coolant again- make sure the engine block gets drained
and use 50/50 premix acura approved coolant

doughboi- you never said what promted all these parts replacement in the first place-
did you have an engine overheat situation?
In which case I would have you look for signs of blown head hasket-
look at the oil dipstick- is it overly full and foamy or brown?
look in the radiator- is it brown or foamy?
if so procedd to remove spark plugs- crank engine over- the one with water shooting out is the bad gasket blown point.
Remove the cylinder head and replace gasket- its a bit more than just that, but it does happen

 

right after taking over the car, i ran into some issues with the radiator which showed signs of a failure i.e, coolant seen on the top portion of the rad. and then it started to over heat. Then i went ahead a replaced the rad, problem happened again, so i went ahead to change the hoses and therm. then car was fine for a couple of days then out of the blue it started to overheat once more ... and here i am still after about a month with issues. I have a feeling that it might be a BHG, but i wont know till sat for sure the oil seemed overly full when i checked it before the oil change about 2 weeks ago, but no brown or chocolate milk =) i have some experience with BHG's due to supra's problem =X

i hope its not but if it is just another thing on my list to fix

thanks for the support i will keep u posted

 

I can almost guarantee it based on the facts now- cars are often driven a long time with leaking radiator- then initial head gasket probs--then sell car quickly---

While you are in there doing them- get a thermoblock intake heat spacer/isolater for 100 bucks- nice addition to the TL and helps in hot hot climate areas and hi speed driving

 

problem fixed fan switch was the culprit

 

no head gasket leak also, coolant nice and bright green =) cant believe it was something so small causing all these problems! but i will definitely look into thermoblock intake spacer thanks for the help

 

did you replace this yourself? can you give me some tips on how to replace this? seems like I may have the same issue since I have noticed my driver's side fan was not running...thanks for all the info

 

glad to hear it was simple fix
Keep a close eye on the oil and coolant for any sign of hg damage and leakage-
its often 6 months after temp probs that it occurs

 

NEVER MIND! PROBLEM HAS occured once more!!! Overheating once again !!! i am fustrated time to take it into the delaer... had a few machanics look at it and no one could fig. the problem im thinking its a control mod. cuz the fan runs but its not running how its suppose to and its not a coolent temp sen. because there is no check engine tested the sens. looks fine...... iono taking it in first thing tommrow let u know what is up with it

 

No...had a friend check the switch just pulled out clean went to acura and got a new part and replaced worked fine for a bit but yea same problem let u know how it goes when i get it fixed for good this time

 

so how has it been? was the control module really the problem?

 

head gaskets will blow if they havnt already. get rid of the car if you cant afford the repair. aluminum engines when overheated do not survive

 

It seems that I got the same issue, someone recommended me to use a block sealer liquid. I bought but haven't used it since I'm a little unsure if this could really help (it's a K&W orange can)

do you guys have ever used it? it's said they repair head gasket permanently, stops leaks and seals crack.

could it be a solution?

 

Are you sure that the head gasket is your problem? If so take teh time to fix it properly.

 

how many times did the car overheat? did any of your mechanics check the head gasket to make sure its not blown? do you have a genuine honda water pump? ive seen people run into overheating problems using after market water pumps.

 

i'm going to bring mine in today to check the water pump and fan relays switch etc.. i'll have them check my head gasket aswell really hope that's not the problem, overheats and rises really slowly, changed everything like OP, radiator, hoses, t stat, coolant temp sensor

 

if anybody is having overheating issues and cant figure why after replacing the thermostat..

i cut mine out.

it was the first time i've had a car where the thermostat was ALSO the gasket... so cutting was the only way to bypass.

this is a good way to ensure never having the thermo lock up and block water flow again.

-downside.

if you live in a cold region of the country.. you wont have a heater in the winter.. but you can always buy a new one and put it back in for only 25 bucks or so.. takes about 10-15 minutes to replace tops...

luckily i live in louisiana.. and dont even use the heater in the winter... the heated seats do just fine when its 45 degrees lol.

[IMG][/IMG]

 

so if I bring my car to my mechanic what do I tell him to do cut the thermostat gasket whut? don't really see what the picture is

 

im saying if the problem were to be thermostat issues... you could just cut the thermostat out.. (leaving the gasket of course) i eventually take the thermostat out of all of my vehicles b/c i have no use for it.

just remember to put one back in if you need a heater in the winter..

the part in the picture is the thermostat.. which on our cars has the gasket attached to it...

 

Im sorry but This is just STUPID information. Never take the thermostat out and leave it out. The car will never operate at the correct temp and you can overheat the motor easier with it removed as the fan could never cool whats in the radiator fast enough if you ever sat long enough.

 

funny... never had that problem^^^

how long does one (stupid) have to sit.. i've been in stopped traffic for hours. with AC running.. it aint exactly ideal weather here either.

also it runs as the same temperature as before... nothing more or less.

no point in arguing though.. its just going to overheat i guess

maybe im just extremely lucky with all of my cars

wasnt trying to misinform anybody my knowledgable sensai... but just like you.. i have had others tell me opposite and recommend it for sticking and problematic thermo's... so with that and a zero trouble and zero temp. problems in 7 years after doing this.. i feel very comfortable offering it as an option..

 

and just so we can be clear that im not making this all up. and it IS something people do other than me. i was simply suggesting it. nobody has to do anything when advice is offered... we're all of age here.

this is an exert from an Automotive website concerning taking out the thermostat.

http://www.auto-repair-help.com

 

theres nothing wrong with taking out the thermostat. its much better to run cold than too hot. w/o the thermostat it will just take longer to warm the engine up, your heater will not get warm and you will be in open loop almost all the time and burn more gas.

 

i guess we're both stupid ^

and yes.. it does take longer before it gets to temperature.. but its nothing noticable. and i dont pay enough attention to gas mileage to see a difference..

but those are the only things i can think of that affect the car in any way.

 

we'll my car overheated once since I changed the temp sens, i've had mech's tell me my headgasket was cracked but when I brought it to get it fixed we let it idle for half an hour never and gauge never went up, drove it around with AC and still nothing, later that night it went to to about half way and that's it wtf is the problem should I just swap engine or is repairing it better? i'm at 185 xxxKM not mile

 

if the headgasket ISNT blown it sounds like there maybe an air pocket in the cooling system. depending on where the air pocket is at the time it could over heat or not. but if you keep bleeding the cooling system and air keeps finding its way in then that just confirms the blown head gasket diagnosis; the air is exhaust gas.

the easiest way to nail down a diagnosis on the headgasket is to do a hydrocarbon test on the coolant.