the intercooler failed or failed cylinder head because it coolant leaking into the exhaust side and cause the engine to over heat.
CX-9 Engine overheated
- Thread starter Cboulden87
- Start date
- :
- Canada
What year is your CX-9?
The charge air cooler (intercooler) is air cooled; no coolant involved. It is located below and behind the front license plate.
Do you have dried green coolant residue on the back side of the engine?
Is the engine oil milky appearing? Even if not obviously milky, send an engine oil sample to a testing lab. It'll test for coolant in the oil and engine wear particles in the oil, $35. Here is one good mail-order testing lab: https://www.blackstone-labs.com/tests/standard-analysis/
I'm now carrying a cooling emergency kit to use at the first sign of a rise in engine coolant temperature...a gallon (hope that's enough) of our Asian green antifreeze and Bar's Radiator Stop Leak Tablets (recommended by Bar's Leaks Co. for this situation). It'll require waiting for the system to cool, crumble and dissolve the tablets and add to the system according to the Bar's directions, top off with new coolant, continue to follow the Bar's directions. If needed this should get me home.
Do you have dried green coolant residue on the back side of the engine?
Is the engine oil milky appearing? Even if not obviously milky, send an engine oil sample to a testing lab. It'll test for coolant in the oil and engine wear particles in the oil, $35. Here is one good mail-order testing lab: https://www.blackstone-labs.com/tests/standard-analysis/
I'm now carrying a cooling emergency kit to use at the first sign of a rise in engine coolant temperature...a gallon (hope that's enough) of our Asian green antifreeze and Bar's Radiator Stop Leak Tablets (recommended by Bar's Leaks Co. for this situation). It'll require waiting for the system to cool, crumble and dissolve the tablets and add to the system according to the Bar's directions, top off with new coolant, continue to follow the Bar's directions. If needed this should get me home.
Last edited:
2016, 111k miles
The worry with our engines is if the cylinder head cracks where it carries the weight of the exhaust manifold and the turbocharger. Coolant leaks out, the engine overheats, parts expand unevenly, the head gasket doesn't seal, coolant gets into the oil, the engine is damaged, and you now need a new engine instead of just the new updated cylinder head. Look for this and hope you only have a standard leak of coolant somewhere.
- :
- Plano, Texas, USA
Typical symptom of cracked cylinder head for the 2.5T in your 2016 CX-9.
2.5T Engine Coolant Leaking TSB
2.5T Cracked Cylinder Head/Leaking Coolant Report to the NHTSA
