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2005 Scion tC makes a rough noise when idling in drive and reverse, but not in neutral. Any ideas what it could be? (imgur link to the video)

No idea if it’s the motor mounts. I’m not very familiar with auto repair

I’m initially in drive, then switch to neutral and the sound stops, and then back to drive where the sound starts again

Initially (without knowing there was audio) I was going to say that it was the ubiquitous loose heat shield making the noise. But after listening it sounds as though this is motor mount related.

It also does not sound as though it is a bad sound…its just a sound and may be perfectly normal. Did this noise suddenly start happening where prior it was not existing? If so…this goes along the line of suspecting a motor mount wearing out. If this noise is no more than what we hear currently…you may be able to just do nothing at all and see what happens.

To see if your motor mounts are in sound condition you can do this simple test. Start the vehicle, Open the hood and look to see how much movement the engine is able to gather. You will put the trans in drive with your foot on the brake and give it some gas lift off the gas and repeat…all the while holding the brake so that the vehicle cannot move. Then see what kind of movement you get when in reverse…and finally… Going from drive to reverse…and gassing it in each gear…on and off the accelerator repeatedly. Going from drive to reverse is where you will see the most engine deflection. In drive…foot on brake…on and off accelerator…then into reverse…foot on brake…on and off accelerator… I’m sure you get the idea. You will see which direction the engine tries to move when in drive and also when in reverse… You may notice what looks to be too much movement in one gear or the other and this may lead you to find a worn out motor mount.

I took out the passenger side mount (where the sound seemed to be coming from) earlier today and have a replacement on the way. It seems like the general consensus across a bunch of different platforms I’ve asked is that it’s a mount issue. If the replacement doesn’t fix it then I might just end up dealing with the noise for a while.

The mount I took out doesn’t seem to have any cracked rubber or anything, but it is VERY easy to move around. Like I said, i’m not very competent in auto repair so I cant say if that’s normal or not but it seemed like it shouldnt be that way to me

OK, not a bad start to solve the issue. Keep in mind, the mount you are probably referring to is one of several mounts that isolate the engine vibrations from the frame. Usually there are about 3 or more, so keep that in mind.

Like I mentioned previously, the sound I heard really didn’t worry me much as pertaining to an issue needing resolution. You could probably have gotten away with just leaving things alone, but it is good you are paying attention to your vehicle and attempting to keep things working as they should.

Let us know how the new mount works out

So I put in the new mount and the sound seems to have stopped, but now there’s another sound that sounds like it’s coming from a pulley on my serpentine belt. And there’s a god-awful squealing sound when I move the steering wheel so I have to guess it’s an issue with the power steering pulley or pump… although there was no issue with that before I changed the mount

I’m so lost with this