Coolant thermostat Stuck open
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Joined: Feb 2025
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Coolant thermostat Stuck open
So I've had this code on my 2017 GLS450 (P0128) for a few weeks now. Points to a failed thermostat (failed in stuck open).
I saw there are two ways to do this. One is to replace the thermostat and the housing and the other way is to replace just the thermostat.
Has anyone done the second one successfully? This video on youtube shows this method - seems a lot simpler to do for the issue at hand....are there any draw backs?
87K miles.
I saw there are two ways to do this. One is to replace the thermostat and the housing and the other way is to replace just the thermostat.
Has anyone done the second one successfully? This video on youtube shows this method - seems a lot simpler to do for the issue at hand....are there any draw backs?
87K miles.
