2008 Acura TL Type S mods, J pipe, PCDs, CAI, 3.7 Mani.

Car keeps overheating when AC is on and im Idling or in a drive thru lane. AC only works when driving past 30 and car doesn’t overheat while driving.
Head gasket Job, radiator, hoses, thermostat and water pump have all been done in the past year. ive also burped the system and used a combustion fluid kit and head gasket seems to be holding up. during winter all heat worked well idling and driving and it never overheated. if anyone has any suggestions

 

Have you confirmed your radiator fans are functional?

 

Thats what I was thinking as well. I owned a car back in the 80’s and my cousins detailed the car from top to bottom. This included the engine bay and while it looked great, he accidentally shorted out the cooling fans. Idling or using the AC had the temp climb like crazy. If I was driving - I had no issues.

 

yeah both fans are working

 

You sure?

Everything you describe is screaming failed cooling fans. Let's ignore the overheating aspect since that could be a couple of other things. You clearly state your A/C doesn't cool unless you are driving 30mph+...again....not getting air over the coils would cause poor A/C performance.

As for overheating...you either have air in the cooling system, failing water pump, bad thermostat or inoperable cooling fans. Most likely culprit again would be the fans since things behave when at speed considering most of the other components were replaced already.

 

I just double checked both fans are spinning and operating like normal which is why ive been left stumped as to what it is. unless the fans are starting to go bad and occasionally work but from what ive seen they’re always spinning. I’ll replace both just to be safe but any other ideas or advice is appreciated

 

Water pump is the next guess... somehow your coolant is circulating correctly while driving, but not at idle? Not enough pressure being created by the pump at lower RPMs...?

Not really sure how that would happen, but it explains your symptoms in lieu of a bad fan.

 

Maybe some sort of partial blockage that’s limiting coolant flow and is more apparent at lower or idle speeds? Driving has the water pump at higher RPMs and is sufficient to circulate coolant???

 

use an infrared thermometer to find a blockage in the radiator

 

A few obvious things to verify..
verify the Thermostat is fully opening. or just replace it.
Make sure there is no air in the system.. To do this, make sure you are using the external reservoir/purge tank. And make sure you fill the radiator Only When Engine is overnight COLD.. Then, cycle the car through Hot and Cold heating and cooling cycles and then, verify the fluid in the purge tank stays in the proper range..
Do not let the car rise to full operating temperature with the radiator cap OFF. I guarantee you will have air in the system if you do that.

 

Ive changed the thermostat and I will be changing both fans today. so far it hasnt happened again but the days haven’t been too hot and thats when it usually occurs
question should both fans be spinning when AC is on only my driver side spins when the AC is on the right doesn’t spin

 

if your car is cool, merely turning on the AC won't automacially turn on the Fans. But I think the AC MUST be On in order to have the 2nd fan turn on. Because per the drawing, there is a FAN LOW and FAN HIGH.
And the fans are not just "tied together". Both fans are controlled independantly.. And both FANs have different names on the drawing. 1 is Radiator fan and the other is AC/Condenser Fan.

This is for 2007 TL


Below is NORMAL operating temperature. It literally has never moved for Years... (Except during intitial start up)
2005 TL with a 2007 cluster

 

also make sure you have these installed under the radiator on the cross member thing... It will make a difference

https://www.acurapartswarehouse.com/...1585095&pnc=29

 

Ive had a base model and now a type s my cars have always ran cooler than that

 

Okay that's cool, no pun intended. Haha
But my car is not running hot it's been doing that for like I said since day one I've had it over 10 years since 2007

Maybe that's why your fan is not kicking on because it's not hot enough?
Since there is no temperature gauge as in showing the degrees then what is your sign that it is overheating since your current gauge is below mine?

 

My TL and TLS have always been at this temp

 

So what makes you think it's running hot?

 

these are pictures from wayy back many years ago when I had my old Speedometer. I had 54k and 73k miles. I have 135k now.
Both clusters (05 and 07/08) report about the same termperature..

 

by the way, I am not sure what thermostat you replaced yours with, but it appears the OEM thermostat is 172 degress F.

https://www.acurapartswarehouse.com/...205AT&filter=()

 

that picture I posted is what my car is supposed to be at but when im idling with the AC on the temp will climb to 3/4 of the way

 

ok I see.. If it is getting this hot and the 2nd fan is not kicking on, then you may have a problem with that Fan or the RELAY.
As a test, you could do a temporary swap of the relay with another relay that you know is working.
Also, verify and/or do everything else I said above.

 

another thing to verify is the Fluid in the radiator is OEM fluid. And verify the radiator is not full of RUST. I know that may be petty, or an extreme, but I have no idea about the condition of your OLD Car.. (and mine is older.)
If radiators get a bunch of rust in them, they wont cool the water properly.

 

Here is something you may try before replacing the FAN. Swap out the "Fan Control Relay" with your base TL. But make sure the part number is the same. I do not know the part number.
This is photo #7 as seen on the diagram above.

 

i’ll do that as soon as I can before changing the fans out I appreciate it all the help
All my fluid is Honda oem and I flushed the radiator and didnt seem like a blockage and it didn’t come out rusty which is what i expected since I swapped it last year but at least it narrows down the list

 

Step by step, everything helps diagnose the issue. Chad is all over this with you.

 

I just replaced my temperature sensor today with an OEM sensor.. it look 10 minutes.. Just need the right length wrench. Too long and you would have to pull the battery out or something.
But anyway.. The new temperature sensor is reading EXACTLY the same as the last one at normal operating temperature.
(I also replaced the front cam cap o-ring while I was at it)
I bought this OEM one from

 

so Im having a new issue the driver side fan keeps staying on after the car is off. the temperature gauge isn’t moving up so it appears it isn’t overheating. I checked the relay in the fuse box and it was melted so i bought a new one and it still is staying on after swapping it to a new one.

 

any check engine light? If so, have to read the codes first. But in the drawing below, I think the passenger side is called the condensor fan and the drivers side is called the radiator fan.
Make sure you have the right size fuse in Fuse #11. I cant read the drawing but it should say on the Underhood fuse relay LID.

 

oddly enough the Fan control relay had gone bad again probably just a faulty one. I replaced it when you had suggested it last time. swapped it again and the problem was fixed. I was worried for a sec