Known 2.0L EcoBoost Coolant Intrusion Defect

[Mrs. Moore]

I own a 2017 Lincoln MKC with the 2.0L EcoBoost engine. The vehicle has begun displaying recurring low coolant warnings and overheating symptoms. After researching the issue, I learned that many owners have reported coolant intrusion, where coolant leaks into the engine cylinders due to a defect in the engine block design. This can cause coolant loss without visible leaks, rough starts, misfires, overheating, check engine lights, and ultimately engine failure requiring engine replacement. I am currently seeking a diagnosis to determine whether my vehicle is experiencing the same known EcoBoost coolant intrusion issue.

 

[MattMacMan]

It indeed is a well documented problem primarily with the second generation 1.5L and 2.0L EcoBoost engine family. These engines were in many 2017-2020 MY vehicles. An easy way to tell if your vehicle has this issue is

Top off your coolant. Drive the vehicle. Park it and let it sit overnight. Pop the hood in the morning, check the coolant level, then remove all 4 spark plugs and send a camera/borescope down the spark plug opening into each cylinder checking for standing coolant or a very clean piston. If either are present, check the cylinder walls for cracks.

You can also swing by your local dealership and have them run your vin to see if your vehicle has been flagged for the TSB/CSP for this well known issue and see if youre eligible for a free engine replacement.

 

[Orion12]

I have a 2017 MKC that had the same issue, it was coolant leaking into the cylinders. I took it in on the last day of my warranty and they replaced the engine under warranty. I was told back then that it would have not been replaced for free if I was no longer in warranty which angered me. I do believe I read somewhere that they are replacing these out of warranty now. This was an issue caused with their design so they should be replacing them outside of warranty.

My wife is still driving my MKC after I bought a 2024 Nautilus hybrid reserve 2. The MKC runs great now, no issues.