Nissan Repair Questions? Ask a Mechanic for Answers ASAP
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DEF fluid is Diesel Exhaust Fluid. This is a fluid that saturates the exhaust so you don't get that black smoke. It's a new type of system for Diesels. If you have low DEF fluid, then you will need to have the DEF fluid level set. When you buy DEF fluid, you can't cap it off and use the rest later like washer fluid. Once the bottle is opened, you must use it. What ever you don't use will need to be thrown away.
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