Thread: Strange sounds under load

Growling noise is definitely much more comparable to the sound that my friends car makes. I couldn't think of anything analogous to it but the card thing because it was speed related lol.

By the way, it is almost guaranteed it will make that sound when the car dips, especially when it dips hard and when it's going fast (55 or faster). I swear though, the sound is only very apparent under load. Not when coasting. Granted, the car makes some pretty ****ed up noises when it coasts lol.

So quick question? Short of it snapping, what can go wrong with an axle? I know the CV joint boot can rip and cause disaster there, but anything that can cause it to become loose or have a lot of play in it?

Is that based on of my response or the video?

Also, can anyone confirm that this sound is not the sway bar hitting the exhaust?

that sounds like the dp is hitting the sway bar imo. got longtubes on our 98 z28, makes the same noise under load but its hitting the trans mount instead

I'm going to try flipping the sway bar next weekend to see if it makes a difference. Will post results.

Did the boot of your cv joint rip? It doesn't growl at all, only vibrates and when I am getting into the pedal pretty good.

Bump..

This issue is really bothering me. If anyone can successfully help me diagnose this problem, I will paypal you $50.00. I can post more videos, give feedback on trying various things, etc. It is holding me back from tuning my car once I get the software.

I will try to give another explanation:
If I drive normal or like a grandma, no matter the speed, the sound is nonexistent.
Once I start to get into the throttle (still not into boost yet), the sound is somewhat apparent when turning the car and going over some pretty good dips in the road.
Right around halfway into boost (according to the cheap boost gauge), I am at a pivotal point. What I mean by that is, any less throttle, it makes the wobbly noise from the video, any more throttle, the noise is saturated and it's full vibration.
At full throttle, it almost feels as if the car is being slowed down by this vibration, like the car is not making as much power as it should.

I have replaced:
- Outer tie rods
- Ball joints and control arms
- Struts
- Engine mount
- GMPP Sway bar

I have checked:
- Wheel bearing for play: The wheel shows no play that is out of the ordinary. I jacked the car up and tested it for play, nothing. I put the car in drive when up in the air, no wobble to either wheel.
- Sway bar to downpipe clearance: The clearance looks like it would be impossible for the downpipe of the SD headers to hit the downpipe, based on the arc of the downpipe. They aren't close at all to touching. If it is hitting, that would be serious rotation of the engine.

Notes:
- When I accelerate, the car doesn't wobble until very high speeds, which I am guessing is because it is not aligned and it has tires that were from an accident (flat patch on them). I do not know if the tires have bad belts, but they seem to run fine.
- When I decelerate, there is a lot of induced wobble, much more than accelerating.
- When I brake, it depends on how hard I rode the brakes I am guessing. Sometimes it vibrates hard, sometimes it doesn't vibrate at all.
- The CV joints do not click and the bearings do not growl. But there is definitely some induced wobble when making slight left or right turns on the highway.

Here is a video I have of the sound. It is around 8 seconds up to 15 seconds that the sound is apparent.
https://www.youtube.com/watch?v=GwvT-8-E6LE

Originally Posted by Russosaur

I know warped rotors can cause bad vibration when you hit the brakes. This wobble/vibration you speak of is it like in the steering wheel focused or whole car

Sent from my Galaxy Tab 3

Yeah I think the vibration is warped rotors. I buy the cheapo rotors from Autozone. The wobble from braking is almost never when I don't get on the highway. It's only when I get off the highway or brake on the highway.

Originally Posted by Fivefingerdeathpunch

Sounds like a ****ing horrible misfire going on.

All chopped and cutting in and out.

But that's just from sounds, I'd have to feel it to say anything else.

Interesting.. I may have to try and load a torque interface with only the spark plug misfires on the screen so it's not so latent. Do you think torque would be quick enough to detect those misfires? I never see the numbers increase when I am driving. I could go try real quick. It does misfire at idle and is not tuned.

Also, I don't know if this will rule out the sparkplug idea, but the SES never flashes.

Well that's quite irritating. I set my torque app up to log Misfires 1-6, load, and engine RPM, but it didn't log any of that, so I can't post the csv results. I did look at the screen, however, and saw no misfires.

I do have one thing to add to the sound. There is a very low/dull grind here and there when coasting. Almost like grinding a rock on a grinding wheel or something like that. Like the equivalent of braking when your pads are down to the metal, except it does it when coasting and goes in an out. Could it be the bearings, and they just don't show play because I can't apply enough force?

Also, to answer the question about vibration, it doesn't pick up in the whole car, only the wheels. It's almost not even in the steering wheel. It feels like the wheels are just loosely connected.

A couple of updates..

I got my exhaust sealed at the resonator (about damn time) and the sound persists.

So here's a video of the sound now with my exhaust "fixed". I say "fixed", because ironically, my flex pipe is leaking. Just my luck.

https://www.youtube.com/watch?v=OjjL67R78ug

When I do the U-turn with my blinker on, you can really hear the noise. I don't know if this has anything to do with the sound, but if you listen closely, you can hear my front suspension making a clunking noise over all the small bumps I go over. Big bumps are fine, i know it's not struts or the motor mounts, outer tie rods were done. Could it possibly be the inner tie rods that's causing all of this trouble? Anyways, here's another video of the car stationary that I think relates to this sound.

https://www.youtube.com/watch?v=QrBOvHa7Dow

The popping noise in the video happens when I turn to the wheel to the left after turning it to the right or vice versa. It is much more apparent left to right.

Originally Posted by Russosaur

I wish I could be more help but all that surging and that sound is odd. I could say tranny but i have no good luck I'll be lurking, hopefully you get it solved

Sent from my Galaxy Tab 3 8.0

Hopefully not the tranny.. Although I plan on getting it rebuilt anyways..

Is there anything I could post to give you a better understanding of what's going on? I can maybe try to mount a GoPro in the engine bay somewhere and see if I can localize the sound. This sound is making me go crazy..

BUMP. So I have discovered I can also replicate the noise while the car is stationary. If I put it in drive, plant my foot on the brake, and get into the gas, I get the exact same noise, that is there's a midway point where it sounds like it's grinding, any less there's no grind, any more and it's full blown grinding to the point where it just vibrates. Starting to sound like a transmission issue?

Also, Russosaur, that surging you heard, that was me actuating the gas pedal to get the sweet spot of the noise.

My vibrating, rattling, grinding noise was my resonator coming apart internally.
If you rev it Hard in neutral you should be able to hear it for a second as it decelerates.
Not saying thats your noise but it damn sure sounds like the noise i had.

Sent from my LG-D950 using Tapatalk

Unfortunately I don't have a resonator or a catalytic converter. It's straight pipes to the mufflers.