PO116 - Coolant Reservoir Empty

[NEKExplorer]

My check engine light came on driving into work this morning so when I got to work I puled the code of the OBDII and got PO116-Eng Temp High

Checked the coolant reservoir and it is empty. 1998 Limited otherwise runs fine, I actually figured it would be an O2 sensor or exhaust related code as I thought it was getting a little loud.

Anyway- no sign of where the coolant went, no puddles I have seen, nothing in the oil. Any ideas about what the issue is?

Also- No Toyota dealer within 60 miles so I would love a suggestion regarding aftermarket coolants as there is an auto parts store right next door.

Thank you for any ideas or suggestions.

 

[alumarine]

The code and the reservoir being low could be 2 separate issues.

When the motor is cold check the level in the rad.

 

[TheDurk]

1 - You don't really want to mix coolants, so what you put in, depends on what you have in there.

2- Best choice in an auto parts store is Zerex Asian Formula. I'd start with a full flush with distilled and a clean fill if you don't know what you have.

3 - Simplest explanation is you have a coolant leak and the resultant low fluid caused the code. So I'd do a coolant pressure test before I put new coolant in as you may have to drain to fix said leak. Some parts stores rent test kits.

4 - Worst case is you have Head Gasket or cracked head and coolant is burning, not leaking. White smoke is usual giveaway. Exhaust gas test from the parts store will rule it out.

5 - Consider a Bluetooth adapter and Torque app for your phone so you can read codes and monitor coolant temps with precision. Dash gauge is almost useless.

6- Chase sensor issues only after you rule out 3 and 4.

 

[spmarfatia]

I found coolent tank empty on my 98 4runner. the rear heater core pipes were rusted out under the car, and coolent was lost from there, slowly! Never seen any puddle..

worth checking that..

 

[seabun]

I just went through this on mine. Disappearing coolant. Turned out thermostat gasket was not properly seated. Hopefully it's not head gasket, may have to just check some of the suggested areas and see if you can spot any leaking. Other things I checked: radiator cap (make sure it's holding pressure), hose inlets, hose clamps (too loose, coolant seep out), the water inlet between house and thermostat.

As for coolant, I read everything I could on this site and decided OEM Red is preferred, but seems that Zerex Asian Vehicle Red from an autoparts store is a pretty close substitute. Whatever you get just make sure it's silicate free. Maybe order Toyota Long Life (red) on amzn or ebay and have it shipped to your house? I saw it for sale on both.

Good luck tracking down the potential leak; I know it's frustrating!

 

[spmarfatia]

also a very good point about the radiator cap holding pressure.

I think mine was unknown reason between, the rear heater core lines rusted and possibly loosing coolant and the radiator cap disintegration, resulting in not holding pressure. allowing the coolant to evaporate.

somehow everything under the radiator cap had disintegrated. from the top it looked fine, but there was virtually nothing left under it.

 

[NEKExplorer]

Thank you everyone for your advice and information. Turns out there is a little gasket/valve on the radiator cap that failed and all my collant was being blown out of the top of the radiator and quickly evaporating as it spilled onto the hot engine and radiator areas.

Very, very, very glad that is all it was. I had just put about $1300 in parts and labor into the engine (timing belt/tensioners, radiator, supercooler for tranny, tranny flush, water pump, plugs, wires, valve cover gaskets, thermostat and plugs). Although I do plan to swap the motor eventually, I was hoping to put that off for another 100k or so. It looks like everything is great and this was just a big scare over a minor part failure.

 

[19963.4lsr5]

Thank you everyone for your advice and information. Turns out there is a little gasket/valve on the radiator cap that failed and all my collant was being blown out of the top of the radiator and quickly evaporating as it spilled onto the hot engine and radiator areas.



Very, very, very glad that is all it was. I had just put about $1300 in parts and labor into the engine (timing belt/tensioners, radiator, supercooler for tranny, tranny flush, water pump, plugs, wires, valve cover gaskets, thermostat and plugs). Although I do plan to swap the motor eventually, I was hoping to put that off for another 100k or so. It looks like everything is great and this was just a big scare over a minor part failure.

The rad caps on the 3rd gen 4Runner are the cheesiest caps I ever used. Between 3 4runners I had 3 caps fall apart.


Sent from my iPhone using Tapatalk

 

[AntleredRuin]

Maybe a bit late, but this:
https://www.walmart.com/ip/Valvoline-Asian-Vehicle-Antifreeze-Ready-To-Use-1-Gallon/49660461
Sold in stores at Wally-World, and it's the exact same thing as Zerex.
Both are Valvoline Zerex, just rebadged. Not sure of the reason, but I called Valvoline to confirm.

 

[spmarfatia]

Thank you everyone for your advice and information. Turns out there is a little gasket/valve on the radiator cap that failed and all my collant was being blown out of the top of the radiator and quickly evaporating as it spilled onto the hot engine and radiator areas.

Very, very, very glad that is all it was. I had just put about $1300 in parts and labor into the engine (timing belt/tensioners, radiator, supercooler for tranny, tranny flush, water pump, plugs, wires, valve cover gaskets, thermostat and plugs). Although I do plan to swap the motor eventually, I was hoping to put that off for another 100k or so. It looks like everything is great and this was just a big scare over a minor part failure.

How is the coolant level now?

I replaced my cap a few months ago, and my coolant is still disappearing!!

So, see if you can check again after a couple of months...