Car Noises (Muffler?)

Uncle Long

I've got a 2000 Honda Accord; V6 and dual exhaust.

I drove it about 3000 miles from Michigan through Canada and to Alaska about two months ago. After the stop at customs heading through Canada I noticed that it was really loud. It may have been loud before that but I was driving close to 80 on the expressway so I wouldn't have noticed much noise.

Anyway. The noise level increases rapidly at around 20MPH and increases through 25-30, drops down again at about 35 but only slightly. It's at its loudest around 45 and then drops down a fair deal at around 60. The noise is not there when I'm idling. There are no slippages between gears or anything like that. There is no real vibration when driving, though there is a slight shake to the mirror which could just as well be due to the road conditions.

When I take a hard left curve the noise stops altogether and the thing runs almost silently. I'm guessing that the left muffler has had it. I had an oil-change just outside of Saskatoon while driving through and had them check the exhaust system but they said that it looked alright. I had them just do a quick general check and they said that everything was fine.

What is this?

I'm looking to sell the car because I live about .5 mi away from wear I work and I've put all of a half of a tank of gas in the car in the last two months. The only time I drive it is when I take it on the small stretch of highway we have on the island in order to keep it in driving shape.

Thanks.

EvilMuffin

Do you have any device you could use to capture the noise, no matter how faint. From your description alone there are far to many shots in the dark.

a penguin

Uncle Long wrote: »

I've got a 2000 Honda Accord; V6 and dual exhaust.

I drove it about 3000 miles from Michigan through Canada and to Alaska about two months ago. After the stop at customs heading through Canada I noticed that it was really loud. It may have been loud before that but I was driving close to 80 on the expressway so I wouldn't have noticed much noise.

Anyway. The noise level increases rapidly at around 20MPH and increases through 25-30, drops down again at about 35 but only slightly. It's at its loudest around 45 and then drops down a fair deal at around 60. The noise is not there when I'm idling. There are no slippages between gears or anything like that. There is no real vibration when driving, though there is a slight shake to the mirror which could just as well be due to the road conditions.

When I take a hard left curve the noise stops altogether and the thing runs almost silently. I'm guessing that the left muffler has had it. I had an oil-change just outside of Saskatoon while driving through and had them check the exhaust system but they said that it looked alright. I had them just do a quick general check and they said that everything was fine.

What is this?

I'm looking to sell the car because I live about .5 mi away from wear I work and I've put all of a half of a tank of gas in the car in the last two months. The only time I drive it is when I take it on the small stretch of highway we have on the island in order to keep it in driving shape.

Thanks.

The bolded part is telling. I don't think it's your exhaust if the problem goes away when you turn left. That shouldn't have an effect on the noise if it was exhaust related.

Sounds like it's suspension related. Check the CV joint on both sides One of the boots may be torn and the joint could have crap in it. If that's the case, you have to replace the joint.

Lord Yod

What kind of noise is it? Clicking, rubbing, just a really loud engine noise, etc?

Nitsuj82

Could also be your catalytic converter has lost its guts. Further description of the sound is definitely needed.

Gafoto

Try visually inspecting it first with the car off, then on if you can't find the hole. Having the car on lets you feel where air might be jetting out. Just don't touch the pipes with your bare hands!

Uncle Long

I'll look into recording the sound.

It's just a lot of engine noise; kind of like I have a coffee can exhaust. The noise is in response to speed and the rate of acceleration.

I've had a look at the muffler and I had the CV joints checked out when I took it in for the oil change (after it was making the noise. The oil change was under traveling expenses for the company that hired me so I had them do a thorough check, but I'll have a look myself) and there doesn't seem to be anything amiss so far as holes.

That catalytic converter suggestion is interesting.

Hopefully I'll sell this car soon, but I want to be able to point whoever buys it in the right direction. If I don't sell it soon I'm going to fix it.

I'll have another look tomorrow when it's light out. Any other suggestions or questions?

Nitsuj82

About the cat, do you smell anything strange?

Uncle Long

Nah, everything is kosher as far as smells. There haven't been any stalling problems either.

This is loud enough that people walking notice it when I drive by; but there is nothing to be heard while I idle. Just want to point that out.

Gafoto

That's pretty normal, even a side exhaust won't sound like much at idle. The cat being clogged or damaged probably wouldn't cause anymore noise than normal. The issue is almost certainly a leak somewhere in the exhaust system.

Uncle Long

That's what I'm thinking. Maybe I picked up a rock and slung it through while on the expressway through Minnesota.
It may have been going before that, but took a wrong hit or something.

Well, considering that I am on an island along the Pacific that sees rain about everyday, I've been told that replacing exhaust components, and especially mufflers, is fairly common practice.

Gafoto

You really are far away from everything.

Uncle Long

Man, there isn't even a road that connects me to everything. That's how far away from everything I am. I have to take a boat or a plane to get to anywhere. Which is why it's silly to have a car.

Though living in a rainforest is pretty alright all in all.

Gafoto

But I bet you can drive insanely fast around the island. There can't be too many cops.

Steve Bennett

You need to determine if its engine related (exhaust, even transmission) or chassis/suspension. You can do this by taking it up to speed to the point where the noise is evident, then putting it in neutral and coasting (letting the engine revs drop to idle). If the noise remains, its chassis related, if its gone, its engine/transmission/exhaust.

Uncle Long

Huh, well, it could be chassis related then. The noise sticks around when it's neutral, so long as I'm still at speed.

I'll have to get under it tomorrow and have a better look when it's light out. Any advice?

Nitsuj82

You can almost always smell an exhaust leak. Otherwise, the sound shouldn't be too hard to find.

Also, consider an aftermarket stainless system if you decide to keep the car in a tough sea air climate.

a penguin

A 2000 Accord would probably throw a code if the cat was bad. I know all of my newer cars have had pre and post cat O2 sensors, as to be even more whiney about emissions.

Dunno if an Accord has those though, just food for thought.


Erm....wheel bearings? I dunno man. Could be some random bearing having a bad day.

Good luck, and tell us what it was when you get it figured out.


edit: fixed model year number. Doh.

Lord Yod

a penguin wrote: »

A 2006 Accord would probably throw a code if the cat was bad. I know all of my newer cars have had pre and post cat O2 sensors, as to be even more whiney about emissions.

Dunno if an Accord has those though, just food for thought.

Definitely does. Is the Check Engine light on? (Yellow light that says Check I believe on that model) If yes, take it to a shop.

Erm....wheel bearings? I dunno man. Could be some random bearing having a bad day.

Very possible. You said that the noise only depends on vehicle speed, not engine speed? (It goes away when the vehicle isn't moving, but keeps going when in neutral on the highway) And it goes away when making left turns? It could be one of your left side wheel bearings going out, as these get unloaded (don't have weight on them for the most part) during left turns.

An easy way to check wheel bearings is to jack the car up, one corner at a time, (CAREFULLY - check your owner's manual for instructions) and then grab the whole wheel at top and bottom and try to shake it. It shouldn't have any noticeable play, as in it shouldn't really wiggle at all. If it does, your wheel bearings are going out. (If it does this, take it to a shop immediately)