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Q: Can driving your car in ocean water affect mpg

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I drove my car in the Oregon coast and washed my car right after. A few days later I took my car in for an oil change and right after that my car started giving me dramatically reduced gas mileage. I went from averaging 32mpg to barely 21mpg and I have a 2016 Subaru Outback. Help!

My car has 20000 miles.
My car has an automatic transmission.

Hi there:

Anytime you drive in salt water, it can cause serious damage to electrical components, suspension components or any seals, gaskets or rubber parts. Even if you wash it off quickly, saltwater can collect on electrical sensors that impact the operation of your engine systems. In some cases, the issues of MPG are caused by saltwater getting inside the air filter; which will sometimes trigger an error code and illuminate the check engine light. The best advice I can offer is to have a mobile mechanic complete a car is getting worse fuel economy inspection so they can inspect your Subaru to see if there are any indicators of damage that might be causing this issue.

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