Recently I have heard a rattle when my car reaches 60MPH. I thought it was something in my glove box, that is what it sounded like. The next time I had the heater on so my friend said it must be the fan. With everything turned off, it still happens and more frequently. A friend who claims to be a car guy (but has been no help thus far) tells me the fan runs continuously even with the heater and defrost off. Is this correct?
I started to investigate, but it is getting a little chilly up here in Canada for me to be ripping apart the housing under the dash to see what is happening. I unplugged the wire, hoping this won't hurt anything.
Thanks for any advice offered
Lisa
1963 Valiant

I can't help with the rattle, but the heater fan doesn't run full time, only when it is turned on.

Welcome to the site!

The rattle could be many things. I wonder if you could record it and post a video/audio? If the rattle doesn't change with fan on or off, then it cannot be the fan. No, it does not run continuously. A key to finding rattles (or diagnosing anything) is to make changes or tests to the car (experimentation). Sometimes dash or door panels or trim can cause rattles. If it is really loud it could be something in the drivetrain (engine, trans, rear), or maybe the wheels/chassis. Does it change with engine speed, or with car speed only? Does it change if you are in 3rd gear vs. 2nd gear? If it is an automatic, you can shift to 2 (do not overshoot to 1!) at 60 MPH and see if the sound changes.

Diagnostics is one of my favorite topics...

Happy hunting!

Lou

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Home of Slant6-powered fun machines since 1988

This comes a little, late but when you can hear the rattle, place your hand on different parts of the instrument panel. Can you feel the rattle stronger in some places? I’ve been having a rattle for years in my 65. It was driving me crazy. This fall I happened to notice that when I moved (placed my hand on) the heater levers, I could feel it. And the sound quieted down when I held the levers in place. It was getting too cold for me too to do anything about it before the winter, but now I know where it’s coming from. Maybe this helps.