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Fast idle when sitting at a stoplight

My car recently started making a rattling noise and idling very fast when stopped but in gear. If I put it into neutral the idle slows right down. Seems normal when moving too. Just want to make sure it’s safe to drive to Cleveland from Detroit.

No one can tell you remotely whether or not your car is safe to drive. This is especially so since you have said nothing whatsoever about it. You didn’t even post a year or mileage, let alone anything about it maintenance history.

A shop that I use regularly does what they call a “trip check” for about $75 - it’s basically just a once over of the major & crucial systems. Maybe you should just have something like that done at a reputable, local shop.

As for the fast idle, that’s the kind of thing that could be checked at that time. Two possibilities would be a vacuum leak or a sticky idle air control valve (IAC). I believe that many Saturn models also had intake manifold leakage problems - that would behave like a vacuum leak in many respects.

Going to Detroit is never safe.

Wow, I mistakenly thought that someone with some helpful advice might comment.

I have no idea why you did not find my comment helpful.