"Popping" noises going over bumps
 

My BRZ goes over bumps and I occasionally hear a "popping" sound coming from the engine bay, it sounds like some suspension or frame component. I think it's the engine braces just behind the intake manifold but I've checked the bolts and they're secure on there, and I have no idea where it's coming from.

It's gotta be something in the suspension because it only happens if I go over a bump, or a small pot hole or similar, all other times there's nothing, no groaning or anything.

Anybody have had this issue?

-RyanG

Are you on stock suspension?

No, H&R sport lowering springs.

Lowering springs will sometimes cause a popping or creeking noise to be present in rough / bumpy road conditions. Sometimes this is because of the "Bump guard" and sometimes this is because the suspension is physically that much stiffer than stock. There are other reasons too, but even when installed correctly they can rattle, pop, and creek

I'd also suggest you check the 3 bolts/nuts on your struts where they connect to the body, inside the engine bay. When you changed out your springs and re-installed your struts, did you Loctite the 3 nuts that secure the top of the strut in the engine bay.


When your car is sitting still the strut will appear fine but hit a bump and literally your strut will be popping/slamming into the strut tower mount/body.


This may or may not be the problem.


But if the nuts are loose, secure them with blue Loctite.


Another side note I believe the nuts that secure the strut to the body/tower should be only tightened to around 20ft/lbs. I happen to know for a fact thatif you decide to tighten them a little tighter to say 30ft/lbs, you will shearer the bolt on the top plate of your strut.


I hope this helps.

bad engine mount? or maybe check all the bushings in the suspension.

that's weird, ive never heard of a complain of a "popping" noise with suspension (springs or adjustable coilovers). usually its some sort of clunking or creaking

I actually have this identical problem. I to have lowering springs. I realized the clunk this weekend on a long road trip. I am looking into it tonight. I will post my findings in this thread tonight.

I haven't always had this popping noise either, it only started about a week ago, and I've had the springs on for nearly a year, and the last time I did anything to the engine bay I repainted the strut braces and I put them back in, I looked at them and tried "jerking" them to see if they were loose when the popping started but wouldn't budge. Also I put them in many weeks before this popping started.

-RyanG

neither of these reasons are even remotely responsible for audible popping noises.

Our problems are sounding more and more eerily similar. I too installed springs almost a year ago.

Remove strut bars and try going over bumps to see if it makes the same noise. Maybe check your endlinks to see if there is any play/corrosion and retighten as necessary

Stock sway bars?

If not stock, then pull the front bar and lube the bushings.

Stock tophats?

I haven't changed anything to the suspension other than the lowering springs. Everything else is stock. Perhaps where the shocks attach to the engine bay frame is broken?

-RyanG

that's the top hat. try raising the car with the tire off the ground and see if there's any movement on the spring/strut body while the car is being raised.

Doubtful. More likely its just a loose bolt. Id go through the suspension and tighten everything.

THIS - They wont move while the car is on the ground, but raise the car and check and that should at least let you know if that's the issue.

I'll check it out and let you all know!

that's not a fact but you are correct- they require very low ftlb

anecdotal =/= fact just friendly fyi :)

Excuse the hell out of me. :lol:since you offered so much, I'll rebuttle with a reply I was given from a toyota master mechanic.

"Ok, Commonly bushing, grommets, and gaskets are the cause though if you're using a fluid shock and not gas, over full / under full (Loss of fluid or improper rebuild) may cause a squeeking, creaking, or popping noise as well. If you did the suspension yourself and had to adjust the "bump guard" cutting it too short *WILL* make this noise though is it usually described as a clunking. In addition, poor alignment of sways, end links, and such depending on various year model and makes could cause such issues. It's be to attempt to isolate the sound best you can and from there check to see if you're suffering from any fluid loss from struts, packing / oil / grease loss from things such as CV boots, and check the sway bar to see if you see any impact points. Hope it helps."

Ahh Semantics. Well, what I can say for sure is (in a friendly tone) is that when I reinstalled mine, with my torque wrench set to 30ft/lbs. The damn bolt sheared. It sucked and I had to wait for the parts.


So yes, I would check your service manual or reliable source. But I personally would not approach 30ft/lbs.


I know that Ohlin specifically mentions 18ft/lbs for their Road and Track coilovers.


That's it though, that's all my knowledge. I hope you find the problem.

a spring compressing or a piece of rubber compressing will not make a "popping" noise, which is more likely a binding somewhere, an over or under tightened bolt or interference.

a spring will only force a pop if it was seated incorrectly, the spring itself is not going to pop

a bumpstop is certainly not going to be making any noises




I don't know what your master mechanic is trying to say, but his answer is rather broad. Why is he talking about rebuilt shocks?

I got my car back from a shop once, heard a funny noise from the front. I took off my front left wheel and found out one of the bolts to the strut was VERY loose. I sat back in disbelief for about a minute...then proceeded to check every bolt on the car that they had contact with. I found another one that was stripped and loose. Scared the hell out of me.:(
Yeah, so definitely do your rounds of investigation before driving a whole lot...

I didn't know a Toyota master mechanic was an expert in fluid dynamics and a shock engineer on the side.

My clunk ended up being that I was missing a caliper slide bolt and the other was loose. Check those out.

Totally OT, but whenever I scroll through suspension sub thread, popping was not the first thing that I thought this thread said lol.


Improper spring perch, some nuts might not be torqued properly (this however presents itself as a clunk rather than a pop). The first thing that comes to mind when I hear the sound of a pop is a binding of some sort.

If it is a popping noise, something is loose.

If it is a pinging noise, your spring is moving around.

-alex

Also I had a popping noise and it ended up being a failed rear axle nut. It was still torqued to spec, but when it was punched it just warped too much and it allowed some movement. Raise the car up, losen enverthing, put the vehicle on its full weight, then tighten everything to spec. If you torque without weight on the suspension you will get a binding pop from bushings, etc.
[ame="https://www.youtube.com/watch?v=PpjrnQQC8ac"]BRZ Axle Nut click - YouTube[/ame]