Mystery Coolant loss - check this
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Joined: Jan 2020
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2018 E400 Wagon
Mystery Coolant loss - check this
So recently I switched from a 18 E400 to a 2021 E53.
I started to get coolant low messages in the morning, at the 60k service they changed the coolant so I thought maybe some trapped air was coming through the system. Topped off the coolant bottle 2-3 times and start to think something is leaking...but I never see any coolant nor any signs of dried coolant around the reservoir or anywhere else under the engine cover.
Decided it was time to go to the dealer...after $300 they found that the heat exchanger for the heated washer reservoir was leaking and filling the washer reservoir lol. I kind of feel that since most washer fluid has anti-freeze additives that the system is a bit redundant but whatever. It never crossed my mind that the coolant was being pumped into the washer reservoir!
$1000 for the new washer reservoir and heat exchanger.
I was worried it was something more serious like a head gasket, but in some ways I’m happy about this fix.
I started to get coolant low messages in the morning, at the 60k service they changed the coolant so I thought maybe some trapped air was coming through the system. Topped off the coolant bottle 2-3 times and start to think something is leaking...but I never see any coolant nor any signs of dried coolant around the reservoir or anywhere else under the engine cover.
Decided it was time to go to the dealer...after $300 they found that the heat exchanger for the heated washer reservoir was leaking and filling the washer reservoir lol. I kind of feel that since most washer fluid has anti-freeze additives that the system is a bit redundant but whatever. It never crossed my mind that the coolant was being pumped into the washer reservoir!
$1000 for the new washer reservoir and heat exchanger.
I was worried it was something more serious like a head gasket, but in some ways I’m happy about this fix.
Last edited by hurddawg; Yesterday at 07:46 PM.
