Popping sound in rear

[JJHLex14]

I’m trying again to find out the problem I am still having. Previously posted in 2023.

My 2014 RX350 with less than 59000 miles.  I have a popping sound driving on normal residential streets at under 30 mph. It is different than the road seam tire noise. Don’t hear at speeds over 45.  It is hard to tell if rear right or left side. I can reproduce the sound if I stand on the bumper and push up and down. Not as loud as when I am driving but can still hear it. Do not hear when going over big bumps.

I do not hear going in reverse as someone asked.

I have had it to a very reputable shop that has been in business for 45 years with a 4.7 star rating 2.7K reviews. I have taken other cars there. They are very honest.
They replaced the sway bar and ends. Checked the shocks and tightened what ever they could. Nothing they did helped. In the end they put my old parts back on and didn’t charge me anything.

 I have also rotated the tires.

My friend who is very good with cars crawled underneath with his Stethoscope as I bounced the vehicle and couldn’t tell where the sound is coming from.

Anyone else had the same issue or ideas on what it might be. I am getting close to taking it to a dealership.

[RX400h]

Quote

The popping sound you’re hearing from your 2014 RX350 could be due to a few different issues:

1. Timing Chain Cover: There have been instances where the timing chain cover needed to be replaced due to oil leakage. If the replacement was not done properly, it could potentially cause a popping sound.

2. Front Suspension: Some Lexus RX models have been reported to make unusual sounds (like a knocking noise) when driven over small humps or potholes at low speeds². This could be due to issues with the shock absorbers or other suspension components.

3. High-Pressure Fuel Pump: Some models have exhibited a chirping noise from the high-pressure fuel pump at idle. While this is typically described as a chirping sound, it’s possible that it could be perceived as a popping sound.

4. HVAC System Fan: There have been cases where the HVAC system fan made a noise due to wear or debris coming into contact with the fan blades

 

[JJHLex14]

I have had the timing chain cover replaced and had it back to rhe dealer because they didn’t tighten everything.

I will probably take it back again. Have to pull out the paper work.

The sound travels back to the rear?

thanks for the ideas.

[JJHLex14]

Doesn’t the car need to be running to make any sounds from numbers 1, 3,and 4 that you listed?

I can stand on the bumper, bounce and hear the sound. I can even push th on the bumper with my weight and rear it.

if not the rear sway bar and end or the shocks which have been checked. What else could cause a popping sound?