09 Taco With Leaking Heater Core

I have a 09 Taco double cab 4x4 TRD with around 72k miles that I noticed had fluid dripping on the passenger front Weathertech floor mat. The fluid felt like coolant and I can also feel the fluid up in the dash leaking on components. My extended warranty runs out in three months so I made a appointment with my local Toyota dealer to get this taken care of.
From what I have seen on the forums the heater core does not seem like a common item to start leaking? Anyone else have one go out? The service writer said he could only remember one heater core on a 1st gen Taco go bad in recent times.

 

Is it definitely coolant?

It's easy to pull the glove box to get a better look back there.

I just had a leak on the passengerside too which turned out to be the captive nuts in the roof for the Oem roof rack. Water was leaking in there and the door seal was acting like a trough to route the water behind the dash and then soaking the carpet and weathertech mat.

Good thing you have a warranty..

 

No you are the only one this has ever happened to.......It happens. Just get it fixed.

 

This problem seems to be model-specific. Isuzu had a lot of heater core issues with their Rodeos back in the 90s. The pipes coming out of the core and into the engine bay area were made of plastic and would easily crack. I suspect Toyota's fabrication is better, but as stated, this happens.

Many designs require removal of the entire dash and some require evacuation of the vehicles a/c refrigerant as the heater core sits in front of the a/c evaporator, also requiring removal of the a/c evaporator.

Hope the dealer you are working with is not like a lot out there who will go out of their way to balk at this repair.

The '05 2nd Gen shop manual has been posted here in a lot of threads. You can browse thru it and get a feel for what's involved.

Here's the online version:

http://www.customtacos.com/tech.old/files/05FSM/repair.html

 

This^. I had one of the plastic levers break off on the HVAC box and had to go into it to replace one of the air mix flaps. Its been awhile but the entire dash, and I mean every last thing down to the steering and pedals has to come out to get to it. Someone who has done this without having to strip out absolutely everything feel free to correct me, but it was one of the worst jobs I have ever had to do on the Taco.

Not trying to be a downer but there are so many clips, wiring clamps and bolts that have to be removed that there is no way that they are all going to be replaced properly and it may rattle. Knowing what it entails, if this were my truck with that many miles, and I were planning on keeping it, I would probably automatically have them do the A/C evaporator as well but that's just me.

Best of luck to you.

 

Sure looks and feels like coolant instead of water to me, plus it leaves a residue on the mat that clean water would not.

 

Got a call from a Service Writer at the Toyota dealer telling me that the tech could not find anything leaking but he did top off the low coolant bottle. The Service Writer also told me that the tech said that what was leaking looked like someone sprayed some kind of lubricant up under the dash. No one but me is in that Taco and I am not in the habit of spraying lube willy nilly up under the dash.
What gets me is that the pipes for the heater core look like they are on the driver's side of the firewall and the leak is on the passenger front compartment. The fluid that is leaking seems more like oil than coolant, maybe it is oil/Freon from the AC system? Next step is to borrow a buddy's bore scope and look under the dash and possibly inside the AC vents for signs of what is leaking. I did pull the glove box door before I took the Taco to the dealership and could not see anything that was leaking.

 

Hmmm, this changes things.

A couple of possibilities here.

On the passenger side the A/C lines pass through the firewall and enter the evaporator that is inside the HVAC box. The evaporator sits in a shallow tray that collects condensation. The tray in turn is drained by a small rubber pipe. Open the hood and go to the passenger side. See the two aluminum pipes in the firewall that have the shared black rubber grommet? These are the A/C pipes. From that black rubber grommet follow downward toward the ground along the firewall about a foot. See the small short rubber hose coming out? That is the drain on the tray sitting below the evap. Any drips or oily stuff on the end of the hose?

Also, on the passenger side at the cowling next to the windshield wiper is the air inlet grill for the HVAC system. Below the cowling is a great place for water to collect. The air passes downward into the HVAC box and then passes through the cabin air filter (behind the glove box). Take out the cabin air filter and with a mirror and flashlight see if the filter looks wet.

Finally, you can not see the inlet/outlet pipes of the heater core from the passenger side. However, in the HVAC box the heater core is plastered right next to the evaporator. Maybe a very long shot here but it might be possible that a pinhole in the right location of the heater core could send a small amount of pressurized coolant backwards through the fins of the evaporator, or be blown to the right side heater duct. Anything wet at the right floor vent outlet?

 

I have seen a Tacoma where there is grease leaking out of the heater servo lever area. This is nothing wrong just the heat of the heater causing some grease to melt and drip out. Wiped it all down with cleaner and it never came back.

As you stated the pipes for the heater core are on the drivers side.

 

Forgot to mention that I did check the AC drain tube and there was a small trickle of fluid (water) draining so it is most likely not plugged.
I also pulled the cabin air filter and looked around inside that area and could not see anything, will investigate it more when I get a borescope. The cabin air filter was dirty but dry so I replaced it.
When I get the Taco back I will take a picture of where on the mat the leak is.

 

Sorry to revive an old thread but did you ever resolve the issue? Im having the same issue right now.

 

Never had any more problems, the tech did not find anything and I have had no other interior leaks on the passenger floor. My warranty has since run out so hopefully I won't have more problems.

 

Which issue? Different things have been discussed, you mean leaking heater core and if so what are the symptoms?

EDIT: sorry, OP must have been posting about same time.

 

The leak in the passenger side. Wondering what it was. I have an oily residue like the op has. Also my coolant was low but it has been 3 years since i did a coolant flush.