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So I've had a coolant leak for a while but it was really slow so I would just top it off but but it seems to be leaking at a faster rate now , mechanic sent me this picture when i took it for an oil change but he couldn't find the location in the limited time he had. I'll probably have to take it back but I just wanted to see if anyone else has experienced something similar.
My 2013 developed a pin hole leak in the plastic water distribution tube that runs across the passenger side of the engine next to the valve cover. It was impossible to find without the engine running and warmed up. If your ‘15 still has the M271 EVO engine this rather common problem could be the culprit.
BTW—
If you know how to use a socket wrench, you can change it yourself in 15 minutes.
Last edited by Odd Piggy; May 22, 2026 at 11:35 PM.
Assuming its one of the M271 engines. Check the lines that hold coolant at the rear of the engine since thats where the coolant is showing up at the bottom of the car. Feed line on passenger side cylinder head as noted above. Check coolant lines at firewall that go to the heat exchanger in the dash.
I would have the engine running and heat turned on.
I see a hole at the bottom of the torque converter housing. Usually there is a rubber plug covering it. May want to check if there should be one installed. May be part# 2222710080.
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