Radiator Coolant Loss (2020 CX-5)

[Pitter]

My bad, I haven't paid much attention to temperature as it was always fine but recently while parked for a moment the engine started running at a high RPM. Checking the gauge I saw the needle was definately higher than normal though well below the red zone. The next day with the engine cold I found I needed to add maybe half a quart of antifreeze. I also noted that antifreeze had splashed out on lower components at some point with green coloring on them but not currently. I'll have to pin that down but it seems the engine sensors know when things are getting too hot and crank up the RPM to cool it down. A new one for me.

 

[Silly Wabbit]

You might have a cracked head and it's leaking coolant. Continue keeping an eye on your reservoir

 

[Jmaz]

I don't see where a 1/2 quart low would be detectable or cause an increase in engine temperature. That's not that much in a ~ 2 gallon system. I suspect something else was the cause.

 

[yrwei52]

My bad, I haven't paid much attention to temperature as it was always fine but recently while parked for a moment the engine started running at a high RPM. Checking the gauge I saw the needle was definately higher than normal though well below the red zone. The next day with the engine cold I found I needed to add maybe half a quart of antifreeze. I also noted that antifreeze had splashed out on lower components at some point with green coloring on them but not currently. I'll have to pin that down but it seems the engine sensors know when things are getting too hot and crank up the RPM to cool it down. A new one for me.

Unfortunately like @Silly Wabbit said above, your 2020 CX-5 with a 2.5T could be a victim of cracked cylinder head due to the external force from the exhaust system when driving over bumps, and your daily trip seems to involve some rough road.

DESCRIPTION
Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold (as shown below). There may be cracks at the stud bolt hole (1) or at the outside of the exhaust manifold flange (2) on the cylinder head.

Cracks may be caused by:

• Expansion characteristics of the exhaust manifold during usage causing unexpected force to certain areas of the cylinder head.

• Residual stress generated during produbction in the cylinder head material may be greater than expected. The external force from the exhaust system when driving over bumps may cause unexpected force to certain areas of the cylinder head.

To eliminate this concern, the design of the exhaust manifold gasket and the cylinder head has been modified to reduce the force on the cylinder head.

TSB No.: 01-002/23 Coolant Leaks at Cylinder Head

 

[wlong01]

If you're still under warranty take it in and let them check it out.

 

[Mazdiod2]

I also noted that antifreeze had splashed out on lower components at some point with green coloring on them

Not good. Is the water pump leaking?

 

[Pitter]

Thank you all for helpful suggestions. I'm going to take it in to Mazda as soon as I can get an appointment. Unfortunately not under warranty.

 

[yrwei52]

Thank you all for helpful suggestions. I'm going to take it in to Mazda as soon as I can get an appointment. Unfortunately not under warranty.

You can show the TSB with pictures of possible coolant leak areas (back side of cylinder head) to your Mazda dealer in case they don’t have such info in Colombia.

 

[Conrad 16.5]

My bad, I haven't paid much attention to temperature as it was always fine but recently while parked for a moment the engine started running at a high RPM. Checking the gauge I saw the needle was definately higher than normal though well below the red zone. The next day with the engine cold I found I needed to add maybe half a quart of antifreeze. I also noted that antifreeze had splashed out on lower components at some point with green coloring on them but not currently. I'll have to pin that down but it seems the engine sensors know when things are getting too hot and crank up the RPM to cool it down. A new one for me.

Was it the engine that you heard running at a high RPM or the noise from the cooling fan running? What did the tach show at the time?

Coolant all over the lower components is certainly not a good sign. It could be a bad hose, if you're lucky, if not...

 

[wlong01]

Thank you all for helpful suggestions. I'm going to take it in to Mazda as soon as I can get an appointment. Unfortunately not under warranty.

Is your Powertrain Warranty still active? It's 5yr/60k in US, not sure what it is in your area.
This sounds like something that would fall under Powertrain unless it's something simple like a loose hose.

 

[Pitter]

 

[Pitter]

Well it turns out tjere is a drip at the junction of the tube with the orange stripe. I hope that is the only source and will find out day after tomorrow when the car is at the dealer. Thanks again to all who've addressed this issue.

 

[HyFlyer]

Well it turns out there is a drip at the junction of the tube with the orange stripe. I hope that is the only source and will find out day after tomorrow when the car is at the dealer. Thanks again to all who've addressed this issue.

That looks too big to be a coolant hose ... Isn't that induction charge air from the intercooler to the engine? That would NOT be a good place to have a coolant "drip" from at all

May be just my perspective looking at the pic

 

[Pitter]

Yes worrisome!

 

[cz5gt]

Could be the plastic box (it is a small coolant reservoir with a cap) has split. Its plastic and that ages faster from the heat over time.
That is not the air from the intercooler. Both the large and small pipes are coolant connected in that reservoir.

 

[Pitter]

The flat lid with integrated tube to the right of the orange stripe is apparently the culprit. Of all things has to be imported from the US. 20 days.

 

[wlong01]

The flat lid with integrated tube to the right of the orange stripe is apparently the culprit. Of all things has to be imported from the US. 20 days.

Seems like luck was on your side. Could of been a lot worse.
Sounds like you can still drive it.

 

[Pitter]

Yes I can. Just have to watch the coolant level until replacement .

 

[cz5gt]

Yes. thats a weak spot (the small plastic reservoir) on all the Turbo models in hot climates.

 

[Pitter]

Well I have a dilema. I need to make a round trip of about 12 hours in the next week. The part is on order. I'm not sure what you call it but it is the flat topped componanant in the above photo where the tube with orange stripe joins it. Thats where it leaks antifreeze. My question is, is this a componanant that could break open even further on a long drive to the extent that coolant can't be maintained in the reservoir/radiator? I don't mind stopping every hour on the trip to refill but if worse damage to the component can occur on a trip I may be better off parking the car and renting one. Anybody familiar with the component mentioned and its weakness?