Head gasket blown? 2014 2.5l CX-5

Absolutely do a compression test if you have the ability. Sounds like a blown head gasket. I'm actually surprised a lot more of this problem hasn't cropped up with the high compression and all.

I'm going to check the compression later today but in the meantime drain the coolant doesn't look good.
 

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OK Mazda you win I give up. 25 years of owning cars from Sh*T boxes to BMW's and repairing them all. I am making an appoint at a auto repair shop something I thought that would never happen. Definitely a crackhead or blown gasket may need a new engine just don't have the time or energy to do this. Mazda you win................. Signing off. Better luck to you all out there I hope you don't suffer the fate I have. Thank you all on this forum been of great help in the past.
 
OK Mazda you win I give up. 25 years of owning cars from Sh*T boxes to BMW's and repairing them all. I am making an appoint at a auto repair shop something I thought that would never happen. Definitely a crackhead or blown gasket may need a new engine just don't have the time or energy to do this. Mazda you win................. Signing off. Better luck to you all out there I hope you don't suffer the fate I have. Thank you all on this forum been of great help in the past.
Sorry to hear that. Id go and find a used engine from LKQ, a place Chris_Top_Her has been getting his used parts with good price.
 
I still think it's not a head gasket. Too much coolant in the oil.

You say it's still running? I would just replace what's wrong and roll the dice to see how far she'll go. That all depends if you continued to run it after you detected the problem.
 
Everybody so easily replaces engines, it is crazy.
Just find the broken part, and replace it.
 
Everybody so easily replaces engines, it is crazy.
Just find the broken part, and replace it.
Yeah thiss basically the way to fix any major problems nowadays. Fallen rocker arm? Replace the engine. Cracked cylinder head or head gasket due to overheating? Replace the engine. Rough or slippery gear shifting? Replace the transmission. Thiss how Mazda handles those problems for its warranty service.

Chris_Top_Her has been getting used parts from LKQ and the price is reasonable. For OPs cracked cylinder head or head gasket, itd be cheaper to replace the engine which has unknown (could be overheating?) problems with a used one. Besides, replace the broken parts such as OPs situation could only fix the problem on surface, but may not solve the problem at root.
 
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If there's coolant in the engine oil then you have this slime for a lubricant between your piston rings and the cylinder walls and everything else, I wouldn't trust it. Another engine isn't far off base...
 
Car is fixed. In the end replaced the engine. It was a crack in the cylinder head (less cost for replacement engine from a salvage yard than new head). Best guess on what happened is had a small coolant leak that went unnoticed finally got low enough and caused engine to overheat and cracked the head (I had heat working on previous drive). My fault for not regularly checking coolant level lesson learned and should have pulled over immediately and not driven several miles to the next exit (but stopping on the side of highway in freezing temperatures was a good excuse not too) . Also learned to appreciate more the cars with low coolant and oil sensors as well as a functioning temperature gauge. The temperature warning light does not come on until it sees 250F (120C) maybe it was running hot for a long time just don't know. May move on from the CX-5 after this experience but will still be in the Mazda family still love my MX5.
 
Car is fixed. In the end replaced the engine.

How much did that cost (I assume from the dealership)?

Reason I ask is our 2014 just had to have a new (used) engine too. Ran down the oil to empty (doh!) but no dash warnings and not sure where the oil went... just did an oil change 3 mos earlier. $4500 all in :(
 
Car is fixed. In the end replaced the engine. It was a crack in the cylinder head (less cost for replacement engine from a salvage yard than new head). Best guess on what happened is had a small coolant leak that went unnoticed finally got low enough and caused engine to overheat and cracked the head (I had heat working on previous drive). My fault for not regularly checking coolant level lesson learned and should have pulled over immediately and not driven several miles to the next exit (but stopping on the side of highway in freezing temperatures was a good excuse not too) . Also learned to appreciate more the cars with low coolant and oil sensors as well as a functioning temperature gauge. The temperature warning light does not come on until it sees 250F (120C) maybe it was running hot for a long time just don't know. May move on from the CX-5 after this experience but will still be in the Mazda family still love my MX5.
Glad the car is fixed although its an expensive one. At least you did see the high coolant temperature warning light due to low coolant level, but many CX-5 diesel owners dont have a chance to see such warning light, and the engine is over-heated blowing the cylinder head gasket and / or cracking the cylinder head.

I simply disagree some suggesting the oil level is fine when it drops to the half between Full / Max and Add / Min marks, or the coolant level is fine when it falls to the half between F and L marks. Keep all fluid levels at the full or maximum marks whenever they get checked (unless its due to get changed very soon). This way will simply provide more safety margin!
 
How much did that cost (I assume from the dealership)?

Reason I ask is our 2014 just had to have a new (used) engine too. Ran down the oil to empty (doh!) but no dash warnings and not sure where the oil went... just did an oil change 3 mos earlier. $4500 all in :(
I almost had similar experience on my 2018 Toyota Yaris iA (rebadged Mazda2) 6 months ago. The car went to a Toyota dealer for free maintenance provided by Toyota. Oil got changed and tires got rotated. Oil was over-filled about ⅓ quart which may saved the engine later. We drove it from San Jose to LA and I checked the oil level the next morning. To my surprise theres NO OIL on the dipstick! I added 2 quarts of Castrol Edge OW-20 which brought it up to the half in between Full and Add marks. The total oil capacity is 4.4 quarts for this Mazda 1.5L BTW. Theres no low oil pressure warning light for entire trip. The Toyota dealer claimed the crush washer is cracked which caused slow oil leak at the drain plug (yeah, right)! And I had to be thankful to the tech who over-filled the oil so that the engine could run longer while the plug is leaking!

In theory the low oil pressure warning light should be lit when oil pump cant suck oil due to the low oil level. But in my situation the engine had less than half of the oil (~1.9 quarts) left but we didnt see the oil light. My guess on your disappearing oil is your drain plug was loose and had developed slow leak like mine. Couldnt be cracked aluminum drain plug washer like my Toyota dealer claimed! ;)
 
Coolant sensors measure the temp of the coolant and not the block, so if you're low on coolant the sensor may not have anything to "read" causing an overheat that will go unnoticed. Actually, anything could have caused that cracked block, may not have been your fault.
 
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Coolant sensors measure the temp of the coolant and not the block, so if you're low on coolant the sensor may not have anything to "read" causing an overheat that will go unnoticed. Actually, anything could have caused that cracked block, may not have been your fault.
OP did see high coolant temperature warning light and kept driving for several miles to exit the highway. Id do the same thing especially in the freezing weather. In my experience in the past, over-heating with warning light or on gauge usually wont cause immediate damage. One time wife called saying something is wrong on her 2000 BMW 528i as the steering wheel feels heavy. I had her drove home about 12 miles as the car was only 5 years old with only 28K miles at the time, I didnt believe anything happened would be serious. I was wrong! When I opened the hood, I saw the serpentine belt was in pieces everywhere, so as the small metal ball coming from water pump bearing! Basically that infamous plastic water pump on I6 simply was disintegrated by itself! Of cause all the coolant were lost. And itd been driving this way for 12 miles!

Another recent experience is on the same BMW. The radiator suddenly gave up after the annual state inspection. I had wife brought me 5 gallons of distilled water so that I could drive, add water, drive, add water until I got home.

Dont see any cylinder head gasket damage or cylinder head crack issues after these 2 over-heating incidents.

But I have to suspect something may have already been wrong as the coolant usually wont missing in larger volume without a leak somewhere, including bad cylinder head gasket or cracked cylinder head. Yeah, it may not have been OPs fault because the over-heating could be the result of problem.
 
Compression Pressure test...

Anybody have a DIY link for skyactiv vehicles for:

? How to disconnect fuel (where's fuse or relay?)
? disable ignition (where's fuse or replay?)

:) Pulling spark plug is easy
:) Compression tester could be borrowed at Car parts store
 
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