Faint Tapping Sound, Gone When Applying Brakes

[Jonasterg]

Recently I've noticed a faint tapping (or ticking, or clicking) sound coming from the front passenger side of the car when I'm driving slowly. It's audible when I'm driving next to a wall or other cars; it echoes off of the barrier and I can hear it with my window down.

As soon as I apply brakes, even very gently, the sound goes away. It doesn't seem to affect drivability and the brakes work fine otherwise.

Does anyone know what could cause this issue? Anything to worry about?

 

[dsapper]

Are you sure its when you apply your brakes or is it when you take the load off the engine? Sounds like an exhaust leak to me

 

[charlief1]

Gethe car going and make sure you're next to some sort of barrier where you can hear the noise. Once it's up to speed put it in neutral and don't hit the brakes right away. If you hear the clicking sound still hit the brakes and see if it goes away. Report back after you do this so we can make sure that's what's causing the noise.

 

[Jonasterg]

I'm not sure, but I can hear it when driving slowly through my neighborhood (engine idling) moving at ~5 mph. It seems to happen in sync with the wheel rotation (more frequent when moving faster, even with my foot off the gas).

I'll check again and make sure it's independent of engine RPM.

The sound goes away when I touch the brakes (I think). I'll re-check my assumptions and update in a day or two.

Thanks for the idea.

 

[HelloBozos]

Disk brake caliper retainers ,just tighten them up

 

[novaderrik]

the pads could be bouncing around in the caliper- there is a tab on the outer one that you are supposed to pound down to tighten it to the caliper when you install them, and that weird springy thing that you clip onto the inner caliper that goes inside the piston to keep that one from bouncing around.

 

[RmvBfrFlght]

Check the wheel bearings, they can click when they start to go bad. Last time it was an outer on the passenger side, same exact symptoms.

RemoveBeforeFlight

 

[Jonasterg]

Update: I drove past a barrier in my neighborhood and put the car in neutral. The clicking/tapping persisted from the passenger side (I can only hear it with the window down).

I rolled past the barrier a few times to try different things. With the engine in neutral, I brought the car to a few different RPMs but the clicking didn't change speed. With the engine in neutral, I gently applied the brakes and the clicking went silent. I drove past the barrier in the other direction, but didn't hear the noise from the driver's side very much (still sounds like it's coming from the passenger side).

I'll take the front wheels off this weekend to bleed the brakes. While they're off, I'll check the pads and look for loose parts.

If nothing looks obviously loose (calipers, pads, etc), is there an easy way to check the health of the wheel bearings?

Thanks for all the help so far.

 

[mhogan6]

Update: I drove past a barrier in my neighborhood and put the car in neutral. The clicking/tapping persisted from the passenger side (I can only hear it with the window down).

I rolled past the barrier a few times to try different things. With the engine in neutral, I brought the car to a few different RPMs but the clicking didn't change speed. With the engine in neutral, I gently applied the brakes and the clicking went silent. I drove past the barrier in the other direction, but didn't hear the noise from the driver's side very much (still sounds like it's coming from the passenger side).

I'll take the front wheels off this weekend to bleed the brakes. While they're off, I'll check the pads and look for loose parts.

If nothing looks obviously loose (calipers, pads, etc), is there an easy way to check the health of the wheel bearings?

Thanks for all the help so far.

 

[mhogan6]

Check for a loose brake pad on passenger side.

 

[TurboBuRick]

Don't rule out it being the rear brake. I would check both on passenger side.

 

[turbofrank]

When rear axle lube need changing it makes a clicking noise.

 

[Jonasterg]

Sorry for the delayed reply; been busy lately.

novaderrik, mhogan6, and others were correct. I took off the front passenger wheel and spun the brake rotor by hand. I can see the brake pad moving slightly if I spin the rotor back and forth. I can also grab the pad and move it about 2 mm up and down.

To fix the loose pad, do I just bend the metal tab-things to make them tight against the caliper? Should I be able to do this with the pad and caliper on the car?

If I need to remove the caliper to fix the loose pad, is it simply the two Allen-style sockets on the inside of the caliper? Or are there more fasteners involved?

I appreciate all the help and ideas so far.

 

[RmvBfrFlght]

To fix the loose pad, do I just bend the metal tab-things to make them tight against the caliper? Should I be able to do this with the pad and caliper on the car?

Yes, the two small tabs get bent in to grasp the caliper. Normally done with them in the caliper, a big pair of channel locks help. Can also do it with the pad out of the caliper. Bend the tabs in a little at a time until the pad needs to be forced into the caliper.

If I need to remove the caliper to fix the loose pad, is it simply the two Allen-style sockets on the inside of the caliper? Or are there more fasteners involved?

I appreciate all the help and ideas so far.

Just the two bolts to remove the caliper, 3/8" allen hex.

RemoveBeforeFlight

 

[zeus87gn]

You also need to check and make sure the mounting bolts on the caliper are properly greased.
If the caliper can't float correctly, it will stick and cause the brake pads to rattle.
This will eventually cause the pads to wear unevenly.

 

[Jonasterg]

I tightened the pad tabs this weekend with a 4" C-clamp (didn't have a ChannelLock handy). Didn't need to take the caliper off, just used the clamp on the tab and the underside of the pad. Since the click was in-time with the wheel's rotation, I'm guessing something on the rotor is slightly out-of-round. I may upgrade the front calipers/pads/rotors later this summer if I get the chance.

No more clicking and the car feels good. No bias when braking, everything feels smooth, no clicks nor squeaks nor grinds. (zeus87gn - Mounting bolts looked greased and okay; thanks for the advice.)

Thanks for all the help everyone!