I have a 1999 Grand Marquis/LS and I have one issue that I need some help understanding. My car hums for about a minute then it kills but starts right back up like it never happened. Does anyone out there have a clue to what that could be. It's been put on a machine and the only thing came up was an oxygen sensor,replaced that and it still hums.
It hums because it doesn't know the lyrics. Just kidding. I think there may be something in the air intake system that is sticking shut.
It sounds like it is your idle air controller! These fail very commonly in all different types of ways. I would replace it. It is a cheap part!
Thanks that's very helpful!!
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