M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: flarteri on January 26, 2009, 03:12:04 PM
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My car has always been on the louder side because of the high-flo cat that was installed on it a few years back, but recently (it literally changed overnight) it seems to be like über loud under acceleration or deceleration. it seems like i can hear something like rattle around in the exhaust line sometimes. I'm hoping it's in the exhaust and not an engine prob, but i'm not entirely sure. I have noticed that the engine sounds fine at any constant rpm if i'm just holding the revs, it's just when i blip the throttle that it sounds different.
oh and ever since it started getting loud and raspy i swear it feel faster, which makes me think something came loose and is relieving backpressure...
any thoughts?? i can try to make a vid maybe later today so you can see how it sounds
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I heard somewhere on the forum that the exaust manifold has a tendancy to get a hole near the #1 cyl... might be it? (to check, start engine cold and "feel" around the manifold for some hot air)
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i just went out and started her cold, felt and listened around the exhaust manifold and all was fine...then i went under the car and sure enough where the cat is welded to the exhaust line there is a crack!! so yeah, thanx for the help though...now i just gotta figure out how to fix it...haha!
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Drive it to a muffler shop, tell the guy you have a crack near your cat flange. It can't cost more than like $20 to have some guy weld up a small crack in your exhaust. I think my dad paid $30 bucks to have a resonator cut out and have a piece of straight pipe welded in, a bit more work than a crack. Good luck.
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Awesome!! Thanx guys for all your help, I'm taking her to the muffler shop tomorrow to get it all fixed. I almost wish i didn't have to though...she sounds SICK!!!
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What you need to do now is get the car de-catted, have ONLY the front mid-box and replace the backbox with a cherry bomb. It sounds the mutts nuts, trust me!
My last cherry bomb got run over by a lorry, ended up about 1.5" thick. NOT good! But I'm tempted to get another, a straight pipe is too loud and I've got another backbox, but its sooooo ricer!