2005 civic VP noise on deceleration
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2005 civic VP noise on deceleration
Greetings to all!
I am a long time reader of this forum and have learned many things from the wealth of knowledge that it offers. I am very thankful for its existance. This is the first time that I have not been able to find a suitable answer, hence my registration
My problem is a wierd rattle upon deceleration. The car is a 2005 civic vp automatic transmission CARB legal exhaust. The noise suddenly appeared while on the freeway. It only happens when I take my foot off the accelerator. It happens in gear and in park or neutral. I pulled the hear shields off the exhaust manifold/cat and the noise is still present. I got a piece of aluminum tubing and placed it on various areas on the block to listen for the source and it defenitely is coming from the exhaust manifold. The manifold has 3 cracks. 1 runs from between #2 and #3 to about a 1/2" above the O2 sensor. The second mirrors that crack but runs on the inner side between the block and manifold. The third is across the #4 pipe. The cracks have not triggered any dtc codes and the check engine light has never came on. That is why I am not willing to shell out the $800 bucks just yet. I would like to hear the opinion of someone that knows, first. I have posted a video on YouTube of the noise. Any insight that you are willing to share is greatly appreciated.
[YOUTUBE]http://www.youtube.com/watch?v=VtQNr7kMHt8[/YOUTUBE]
I am a long time reader of this forum and have learned many things from the wealth of knowledge that it offers. I am very thankful for its existance. This is the first time that I have not been able to find a suitable answer, hence my registration
My problem is a wierd rattle upon deceleration. The car is a 2005 civic vp automatic transmission CARB legal exhaust. The noise suddenly appeared while on the freeway. It only happens when I take my foot off the accelerator. It happens in gear and in park or neutral. I pulled the hear shields off the exhaust manifold/cat and the noise is still present. I got a piece of aluminum tubing and placed it on various areas on the block to listen for the source and it defenitely is coming from the exhaust manifold. The manifold has 3 cracks. 1 runs from between #2 and #3 to about a 1/2" above the O2 sensor. The second mirrors that crack but runs on the inner side between the block and manifold. The third is across the #4 pipe. The cracks have not triggered any dtc codes and the check engine light has never came on. That is why I am not willing to shell out the $800 bucks just yet. I would like to hear the opinion of someone that knows, first. I have posted a video on YouTube of the noise. Any insight that you are willing to share is greatly appreciated.
[YOUTUBE]http://www.youtube.com/watch?v=VtQNr7kMHt8[/YOUTUBE]
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Re: 2005 civic VP noise on deceleration
I've heard one other car make that noise (or very similar) in the shop, it was an 05 LX with over a quarter million miles on it.
Did the same things you said you did, eliminated the heat shields and used a stethoscope to listen.
We made an estimate to replace the cat for this noise, but the customer did not want to do the job and traded the car off for a 10 Civic.
Did the same things you said you did, eliminated the heat shields and used a stethoscope to listen.
We made an estimate to replace the cat for this noise, but the customer did not want to do the job and traded the car off for a 10 Civic.
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Thanks for the reply ezone! I have been considering taking it to a muffler shop to have them weld the cracks as a means of a cheap test. But, I'm not sure if welding the cracks would stop the rattle. There is nothing I hate more than spending money on uncertainties. This is so frustrating.
If you think a good mechanic is expensive, try hiring a bad one
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From: Midwest. Aiming about mid-chest
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I don't believe the upper section cracks will make it rattle like that.
I think the substrate (cat element) or its holder (supporting structure, or shell within a shell?) inside may have come loose.
I think the substrate (cat element) or its holder (supporting structure, or shell within a shell?) inside may have come loose.
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If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
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From: Midwest. Aiming about mid-chest
Rep Power: 517 Re: 2005 civic VP noise on deceleration
Yes.
The car I described earlier had no codes at the time of inspection.
"the average 4 cylander" is not relevant.
Every manufacturer/vehicle/engine is different.
You would need to compare yours to an identical car with similar wear and mileage.
Briefly, yes, but don't do it for very long. I have driven cars in and out of the shop with no exhaust manifold. It is LOUD.
Valve damage can result in the long term without a manifold.
The gasket at the cylinder head is steel, you can probably get away with reusing it if you must.
You could pull the manifold all the way out and shake it, if it rattles that would give you a definite answer...But even if it doesn't rattle that doesn't rule it out.
Hey, before you do all that, take your listening device under the car and listen at the pipe just after the cat that runs under the engine. Have someone else in the drivers seat to rev the engine and make the noise. I doubt that is it, but what the hey.
You could also use a rubber mallet to tap on exhaust parts, see if you can make the same tone of rattle. (Don't use a hammer that can dent the shell of the cat itself, you can ruin the element.)
HTH
The car I described earlier had no codes at the time of inspection.
Every manufacturer/vehicle/engine is different.
You would need to compare yours to an identical car with similar wear and mileage.
Valve damage can result in the long term without a manifold.
The gasket at the cylinder head is steel, you can probably get away with reusing it if you must.
You could pull the manifold all the way out and shake it, if it rattles that would give you a definite answer...But even if it doesn't rattle that doesn't rule it out.
Hey, before you do all that, take your listening device under the car and listen at the pipe just after the cat that runs under the engine. Have someone else in the drivers seat to rev the engine and make the noise. I doubt that is it, but what the hey.
You could also use a rubber mallet to tap on exhaust parts, see if you can make the same tone of rattle. (Don't use a hammer that can dent the shell of the cat itself, you can ruin the element.)
HTH
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EZONE!!!!!! My man!!! I pulled the manicat off and sure enough, it was broke on the inside. A bunch of grey epoxy-looking crap came out when I turned it upside down. Thanks a million for your insight!!! Youdaman!!!
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