Another Mystery Noise.....Stumped! Help!
Thread Starter
Intermediate
Joined: Jun 2018
Posts: 41
Likes: 17
From: Detroit
Another Mystery Noise.....Stumped! Help!
Hey guys,
Ive got another mystery noise! Two Actually!
This time from the rear suspension / drivetrain...
Going back in time, I recently did a eurowise lift on my 2013 CD. Chased down a couple noises in the front end afterwards that ended up being unrelated to the lift. Had everything nice and tight, no noises. Solid over bumps, all WAS well for a couple weeks driving it around town...
A couple weeks ago, I loaded up the CD and headed out to the West Coast for a few jobs I have to do...
Day 1, 900 miles. No issues, no noise.
Day 2, drove over a fairly rough area / washboard / choppy pavement of I-76 outside of Denver... (50 miles or so of off and on rough pavement.) When I got to my hotel in grand junction that night, I have the radio turned down when i pulled into the hotel, and thought I heard a "clunk" or thump noise or two when going over some bumps in the entry and parking lot. Decided I was hearing things...
Day3, Leaving the hotel, I heard the same noise in the morning. Decided to pay attention for it going forward to see if it was going to get worse. Got back on the highway, got to LA.
Once off the highway, the noise is pretty constant, over every bump or dip in the road. Once at highways speeds the noise is not noticeable or not there over bumps. But like I said, its mostly constant when driving around town over any uneven surface. There are no vibrations or shaking or anything like felt in the car or chassis when the noise occurs.
At first it almost seemed like the back seat might have been the culprit, but after pushing up and down on the rear bumper it seems to be coming from under the rear of the car. I went and checked all the arms, bushings ect for play with a prybar and hammer. no noise.... or play.
-Checked the strut mount bolts in the boot, all tight and torqued.
-Sway bar bushings and end-links appear fine, no play and rubber intact.
-No play in wheels or noise from hub area when up in the air.
-exhaust is not hitting anything when moved, mounts all engaged and fine.
-every nut and bolt that I could access, or had broken loose before is tight and solid.
**Could it be the strut bushings? On the upper mounts? Axels? Driveshaft?
I was at a friend's yesterday and I had him push the car up and down while I was under the car while it was on all 4 wheels. It made the noise on every push, I grabbed, pushed on and pryed on every bit of the suspension with no luck at changing the noise or feeling any movement.... I am stumped...
I also realized you can hear the noise faintly even with the smallest push of the suspension.
And even with my face a few inches from all the bits under the rear while it was making the noise, I couldn't nail down an area even where it was coming from. It seems to be coming from the center, but when under the left of right side it seemed to be coming from there also. MAYBE slightly more on drivers side....
No idea what to make of it, I have probably put nearly 2000 miles on the car, since I first noticed the noise. It hasn't gotten any worse these last 2 weeks being mostly on city streets and hearing it constantly, its not getting to be louder. there is still no feeling from it. And there are no other symptoms, unless the other noise I started to get is related, as it was around the same time, or maybe a little later that it started happening. also, I'll explain that below...
The 2nd noise is coming from the exhaust, I think.... the Tip on the drivers side I think...
Ive noticed that SOMETIMES, after driving the car, when I am pulling into a parking spot, and put the car in park, this high pitched squealing / humming noise starts happening.
If I change the revs at ALL it stops.
So once when It happened I left the car running, got out and walked around the car. It was quickly apparent the noise was coming from the drivers side exhaust tip.
I put the toe of my shoe up against the exhaust tip and the noise stopped.
Foot off, started again. I did the same thing with my finger, I just applied a little pressure to the tip and the noise stopped.
Yesterday I was thinking it might be the clamp, or the tip angle or something along those lines. So I broke them both loose and adjusted them. Making sure that even some bumps or movement they wouldn't hit the trim, or anything else and were centered in the openings. Re installed and tighten the clamps.
Thought it was fixed, drove it around all day, no noise at all when pulling in and parked.
Then when I got home from a friends house tonight, it did it when I parked in the driveway. Same thing. Put a little pressure on the exhaust tip. No noise. Change revs, no noise.. I am assuming this happens bc you are changing the resonance from the engine vibrations.... anyways. Its annoying, and loud enough to be embarrassing when parking in public haha.
Anyone had this happen before? Are the rivets that hold the brushed metal to the functional part of the exhaust failing or something?
Anyways, seeking advice and or help before these noises make me any more crazy than I already am
Ive got another mystery noise! Two Actually!
This time from the rear suspension / drivetrain...
Going back in time, I recently did a eurowise lift on my 2013 CD. Chased down a couple noises in the front end afterwards that ended up being unrelated to the lift. Had everything nice and tight, no noises. Solid over bumps, all WAS well for a couple weeks driving it around town...
A couple weeks ago, I loaded up the CD and headed out to the West Coast for a few jobs I have to do...
Day 1, 900 miles. No issues, no noise.
Day 2, drove over a fairly rough area / washboard / choppy pavement of I-76 outside of Denver... (50 miles or so of off and on rough pavement.) When I got to my hotel in grand junction that night, I have the radio turned down when i pulled into the hotel, and thought I heard a "clunk" or thump noise or two when going over some bumps in the entry and parking lot. Decided I was hearing things...
Day3, Leaving the hotel, I heard the same noise in the morning. Decided to pay attention for it going forward to see if it was going to get worse. Got back on the highway, got to LA.
Once off the highway, the noise is pretty constant, over every bump or dip in the road. Once at highways speeds the noise is not noticeable or not there over bumps. But like I said, its mostly constant when driving around town over any uneven surface. There are no vibrations or shaking or anything like felt in the car or chassis when the noise occurs.
At first it almost seemed like the back seat might have been the culprit, but after pushing up and down on the rear bumper it seems to be coming from under the rear of the car. I went and checked all the arms, bushings ect for play with a prybar and hammer. no noise.... or play.
-Checked the strut mount bolts in the boot, all tight and torqued.
-Sway bar bushings and end-links appear fine, no play and rubber intact.
-No play in wheels or noise from hub area when up in the air.
-exhaust is not hitting anything when moved, mounts all engaged and fine.
-every nut and bolt that I could access, or had broken loose before is tight and solid.
**Could it be the strut bushings? On the upper mounts? Axels? Driveshaft?
I was at a friend's yesterday and I had him push the car up and down while I was under the car while it was on all 4 wheels. It made the noise on every push, I grabbed, pushed on and pryed on every bit of the suspension with no luck at changing the noise or feeling any movement.... I am stumped...
I also realized you can hear the noise faintly even with the smallest push of the suspension.
And even with my face a few inches from all the bits under the rear while it was making the noise, I couldn't nail down an area even where it was coming from. It seems to be coming from the center, but when under the left of right side it seemed to be coming from there also. MAYBE slightly more on drivers side....
No idea what to make of it, I have probably put nearly 2000 miles on the car, since I first noticed the noise. It hasn't gotten any worse these last 2 weeks being mostly on city streets and hearing it constantly, its not getting to be louder. there is still no feeling from it. And there are no other symptoms, unless the other noise I started to get is related, as it was around the same time, or maybe a little later that it started happening. also, I'll explain that below...
The 2nd noise is coming from the exhaust, I think.... the Tip on the drivers side I think...
Ive noticed that SOMETIMES, after driving the car, when I am pulling into a parking spot, and put the car in park, this high pitched squealing / humming noise starts happening.
If I change the revs at ALL it stops.
So once when It happened I left the car running, got out and walked around the car. It was quickly apparent the noise was coming from the drivers side exhaust tip.
I put the toe of my shoe up against the exhaust tip and the noise stopped.
Foot off, started again. I did the same thing with my finger, I just applied a little pressure to the tip and the noise stopped.
Yesterday I was thinking it might be the clamp, or the tip angle or something along those lines. So I broke them both loose and adjusted them. Making sure that even some bumps or movement they wouldn't hit the trim, or anything else and were centered in the openings. Re installed and tighten the clamps.
Thought it was fixed, drove it around all day, no noise at all when pulling in and parked.
Then when I got home from a friends house tonight, it did it when I parked in the driveway. Same thing. Put a little pressure on the exhaust tip. No noise. Change revs, no noise.. I am assuming this happens bc you are changing the resonance from the engine vibrations.... anyways. Its annoying, and loud enough to be embarrassing when parking in public haha.
Anyone had this happen before? Are the rivets that hold the brushed metal to the functional part of the exhaust failing or something?
Anyways, seeking advice and or help before these noises make me any more crazy than I already am
Addict
Rennlist Member
Rennlist Member
Joined: Nov 2003
Posts: 1,997
Likes: 573
From: Edwardsville, IL
Seems like you check things pretty good.
Noise #1. Yes. My bet is the strut bushing: on top of strut. Happens to some Audis and VW also. No noise at highway speeds. However, you notice it at slow speed, over bumps, and going slowly up driveways.
Double check strut tower bolts. Maybe even loosen the bolts, inspect, and retighten? See if that helps?
Noise #2. You narrowed it down pretty good. The Muffler. Failing internals to muffler? Rust developing around a fitting for gas to seep out?
You have done a good job getting closer to the answer.
I'm confident you will nail it.
Keep us informed on what you discover.
Noise #1. Yes. My bet is the strut bushing: on top of strut. Happens to some Audis and VW also. No noise at highway speeds. However, you notice it at slow speed, over bumps, and going slowly up driveways.
Double check strut tower bolts. Maybe even loosen the bolts, inspect, and retighten? See if that helps?
Noise #2. You narrowed it down pretty good. The Muffler. Failing internals to muffler? Rust developing around a fitting for gas to seep out?
You have done a good job getting closer to the answer.
I'm confident you will nail it.
Keep us informed on what you discover.
RL Community Team
Rennlist Member
Rennlist Member
Joined: Oct 2003
Posts: 7,905
Likes: 892
You did a suspension lift (2" or more?), and did not relax the control arms and re-torque them at the new height? If that's the case, you likely "tore them" at this new position, especially if they are the original parts, and this has likely introduced slop. There are 9 total bushing connections on each side of the rear, to relax and re-torque at the new height. On the rear suspension, the upper front and upper rear control arm bushings tear apart pretty easily and are not easily noticed when checking with a hammer or pry bar (I think that test is rather useless, as it tends to only work if they are completely disintegrated!).
