New exhaust system incl. cat

debutant · Post by **debutant** » 16 Nov 2002, 03:48

3 weeks ago my catalyc converter broke (xantia 1.8i 16v, 1997, 75,000 miles) and I went to the garage to have it replaced. They adviced me to have also the rear box replaced which I agreed on. After an hour and 600 quit from my wallet I went home, but noticed a funny sound on the car. I didn't pay that much notice to it as I was a bit used to the old sound of the exhaust. However, when I drove with my window down and accelerated I sounded like the exhaust system was leaking a bit. Next day I went back to the garage and told them what happened. They made a test drive and checked the system for leak. Everything was fine and no leak at all. They told me that the cat does sound a bit funny when it is new and it will go eventually. Now, 3,000 miles with the new cat, the cat (or exhaust system) seems to get a bit more noisy. You only hear it when you accelerate. When you don't accelerate and just drive the sound is gone. This is the reason I suspect a leak, cause accelaration means more pressure on the exhaust and I would hear a sound when there was a leak!?
Somebody told me it could be that they have installed a cat for a 8v and that is the problem. Unlikely as I had the job done at my Citroen garage.
The sound is kind of like this: when you have a bike and you put a paper with a peg against the spokes and you cycle around. That is simular to the sound I hear when I accelerate with my car.
Today I went back to the garage, but they keep telling me there is no leak.
Does anybody have any idea what it can be? Or how I can check it?
Many thanks,
John

allmond · Post by **allmond** » 16 Nov 2002, 17:16

Hi John
The paper against the spokes sympton sounds to me a bit like a loose baffle somewhere in the back box. I would suggest going back and rather than asking them to look for a leak, tell them to mend the noise in (their) new system. Easier said than done I appreciate.<img src=icon_smile.gif border=0 align=middle>
Jamie

alan s · Post by **alan s** » 17 Nov 2002, 00:28

Option two to go with Jamies suggestion is a leak at the exhaust manifold or front pipe.
Due to back pressure, a leak there at times can almost sound like a mechanical tap & can be made to totally disappear at a certain rev/load range.
Alan S

debutant · Post by **debutant** » 19 Nov 2002, 03:58

Will go back to the garage on Saturday and have it all checked again! I'll let you know about it ... hope the sort it, its getting a bit annoying as they have changed the whole exhaust system. I read once on a topic that sometimes they have trouble with the gasket at the beginning of the exhaust? Seems to be a pain in the a** to get that right.
Ah well, Saturday is the day <img src=icon_smile_sad.gif border=0 align=middle>
Cheers,
John
Dumped my Escort XR3I for a Xantia <img src=icon_smile_big.gif border=0 align=middle>

Xantia786 · Post by **Xantia786** » 19 Nov 2002, 06:11

As Alans says,from the sound of things,the exhaust system is leaking at manifold/downpipe or downpipe/cat.I cant say that i have ever heard of a cat being noisy from new and getting quiter as the miles pass but it is posible i suppose.Did You also have the down pipe from the manifold replaced when they did the cat? A lot of places dont like replacing down pipes as the nuts have a habit of shearing off unless you liberaly squirt them with wd40 and using a blow torch on them.Most exhaust systems are ususally guaranteed at least for a year so best option is to go back and tell em to sort it out.Good luck.
B

debutant · Post by **debutant** » 20 Nov 2002, 02:57

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
As Alans says,from the sound of things,the exhaust system is leaking at manifold/downpipe or downpipe/cat.I cant say that i have ever heard of a cat being noisy from new and getting quiter as the miles pass but it is posible i suppose.Did You also have the down pipe from the manifold replaced when they did the cat? A lot of places dont like replacing down pipes as the nuts have a habit of shearing off unless you liberaly squirt them with wd40 and using a blow torch on them.Most exhaust systems are ususally guaranteed at least for a year so best option is to go back and tell em to sort it out.Good luck.
B

<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
I had the whole system replaced from start to end. The system appears to be only 2 parts anyway: downpipe + cat + pipe to backbox is one set and the backbox itself. I suspect that they didn't connect the downpipe properly, but as mentioned in this topic, it comes with a warranty, so the garage can sort it out for me. If not, I will need a bit more help from you all!
Cheers,
John
Dumped my Escort XR3I for a Xantia <img src=icon_smile_big.gif border=0 align=middle>

debutant · Post by **debutant** » 23 Nov 2002, 04:11

Problem solved!
I took the day off work today as I was getting a bit annoyed with the sound (and fuell consumption!). Went back to the garage, showed the original invoice and mentioned my complaint. Another guy had a look at the car this time and he said from the moment he heard the sound that the manifold was leaking.
They sorted it out and in the end and I didn't have to pay the bill of 65 quit because it was warranty. Car driver as smooth as it used to do!
Cheers,
John
Dumped my Escort XR3I for a Xantia <img src=icon_smile_big.gif border=0 align=middle>