So my guy friend who is going to help me fix my car made a joke saying, “if he shows up again, I might have to drop a nut in the intake”?

What did he mean by this?
So my guy friend who is going to help me fix my car made a joke saying, “if he shows up again, I might have to drop a nut in the intake”?
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+1 y
When he said, “if he showed up again…”, he was referring to my ex.
So my guy friend who is going to help me fix my car made a joke saying, “if he shows up again, I might have to drop a nut in the intake”?
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