hi, i get these noisy clunking sounds at the rear of my 00 civic ex coupe. the thing is, the noise is there only at low speeds. i noticed that it only sounds when the car is cold (parked overnight or parked for a couple of hours), then the noise will be gone after a minute or so. my mechanic told me the sound comes from a couple of things, 1)lower strut bar, the clearance of the bar to the ground is too low, just an inch 2.)the rear seat is not clamped properly 3.) my amp is not mounted properly, and he is kinda blaming it on the aftermarket parts. they already fixed the 2 side rear seat clamps but can't attach the center clamp. the amp seems to be bolted tight- i can't understand how this could make a clunking noise... they didn't do anything with the struts. the noise is still there. do any of you have experienced this? you think it is because of the struts? i've been trying to determine where it comes from for about a month now. thanks in advance.

 

Have your drum brakes checked. I bet thats the cause.

 

that's what I thought at the start, i try pressing on the brakes whenever it sounds but the sound is still there. so i was thinking it is not related to the brake drums. am i right?

in addition, the noise sounds like it comes from the trunk. it sounds like someone is tapping the body.

 

gas tank not properly strapped in?

 

i'm not sure about that. if that's the case, it must sound the whole time. it only sounds at the start for a couple of minutes and won't come back until the next time I start the car when it is cold.

 

You said you have a lower strut bar correct? My friend had a civic turbocharged with a custom built exhaust system and the muffler barely clears the strut bar. Everytime he starts the car after it has been sitting for a while, it make a soft banging noise until it has completely warmed up due to the fact that Honda engines don't like the cold and run rough when they have sat for a while. The banging comes from the odd miss in the firing order due to moisture in the distributor which causes the exhaust system to move and shake more than it is used to, making the muffler hit the strut bar. The noise completely disappears after the car is warm and up to proper operating temperature. Completely noticible from the inside but not at all from the outside unless you know what you are listening for. I have noticed this phenomenon in all Honda's that I have tinkered around with and any type of exhaust that has components that are extremely close to body parts or suspension parts. Again these noises happen only when the engine is cold and the car is moving slow. Another thing to mention, does this noise occur louder or at all when you are turning or braking? A long time ago my front roll bar cracked in it's center and everytime I turned a corner a nasty clunk would happen while braking hard, making and exiting any turn. If I remember correctly, you have a 2000 civic coupe which has independent rear suspension equipped with an anti-roll bar. Get your mechanic(s) to check that out and if you know what you should be looking for, crawl under the back of the car and have a look yourself. These are all problems that would cause any clunking sounds, and make sure that your lower strut bar is completely tight because that would definately make a bad noise if it isn't. Hope this has been of some help.

 

Also, listen to the boss Remmy the admin. Drum brakes will make a clunking noise if they don't seperate from the drum properly before you start moving the car. If they are cold, they will make that noise. Get your wheel cylinders and emergency brake cable tension checked the next time you are at your mechanic.

 

yes, i have a rear lower strut bar. but when i look at it, it doesn't loook like the strut bar hits the muffler. i had that checked too. in your friend's car, does that soft banging sound there when he is just idling? because when i start my engine, there is no noise, but when i start moving, the sound is there. it sounds only at the start, regardless if i'm turning, going straight, etc.

 

So the second you start moving, regardless of engine temperature or revs of the engine, the very second you start moving from a stop you hear the clunk noise?

 

may be a couple of seconds after I start moving. i have another observation, i know this is stupid, about the weather, if its around the 30's, it will sound, today was about 50-60, there is no clunking sound. it is really weird.