Hi All,

I've been trying to chase this popping sound on the front passenger side of my 87 300d for awhile now. Here's a brief overview:

Only on the front passenger side, never the driver side. The pop happens when going over bumps, hard braking (but won't pop again with hard breaking until after I have come to stop, after I've stopped it'll pop again under hard braking, but not again until I stop), turning the steering wheel while idle, turning the steering wheel while backing up and turning (produces a noticeably louder pop). These noises are not consistent neither, sometimes it's all of the above all the time, sometimes there's no sound, sometimes there's a mix.

I took the car into the mechanic and they could not find the source of the sound, though they did find two other things that needed attention. I had them fix those but then took the car back because the bill was getting too high for that month.

All of the suspension and steering components were replaced 3-4 years ago. I asked the mechanic specifically about the ball joints on the control arms (replaced three years ago with lemfoerders) and he assured me the control arms were fine.

In the report, the mechanic mentioned slight play in the idler arm bushing (replaced two years ago, I've had to replace that three times since 2013 due to using cheap parts, last one was lemfoerder). I tested it, but there doesn't seem to be much play.

If anyone could give me advice about what you think the culprit could possibly be, or what more tests I should run, please let me know. This popping sound is driving me crazy, especially since I have been able to successfully diagnose and solve every other problem on my car, thanks in large part to the fine folks on this board.

Anyhow, I was bored so I took a video of me testing the tie rods, center link, and idler arm. Does the play look normal in these? Could these be responsible? Thanks for all the help!

https://www.youtube.com/watch?v=YC7Ou2Y0OEM