No cats = more valve noise?
03-04-2010, 09:52 AM
#1
No cats = more valve noise? DEAR INTERNET,
I have an entirely stock car with an exhaust cutout and no cats. At about 1200 to 2200rpm the car makes a ridiculous amount of tapping noise(free rev, under load, everything), the sound is more of a "rattling tap" and its hard for me to tell what it is because the sound doesnt exist outside of the 12-2200 window. I want to say the car has had this issue from day 1 and its never been too noticeable but since I had the cats cut off its incredibly annoying. Sound is an issue with the cutout open or closed, its just waaaayyyyy louder when its open.
Sound is not audible from under the hood(revving or not), seems to be mostly escaping out of the exhaust area.
Could the sound be an exhaust leak? Wouldnt it always be puffing or making noise?
The exhaust guy unbolted the flange and removed the whole cat pipe before cutting, does the manifold to cat gasket need to be replaced since he pulled it apart?
BONUS QUESTION: Easy way to add diff fluid without a lift?
Thanks LS1tech, hopefully ive given enough information
I have an entirely stock car with an exhaust cutout and no cats. At about 1200 to 2200rpm the car makes a ridiculous amount of tapping noise(free rev, under load, everything), the sound is more of a "rattling tap" and its hard for me to tell what it is because the sound doesnt exist outside of the 12-2200 window. I want to say the car has had this issue from day 1 and its never been too noticeable but since I had the cats cut off its incredibly annoying. Sound is an issue with the cutout open or closed, its just waaaayyyyy louder when its open.
Sound is not audible from under the hood(revving or not), seems to be mostly escaping out of the exhaust area.
Could the sound be an exhaust leak? Wouldnt it always be puffing or making noise?
The exhaust guy unbolted the flange and removed the whole cat pipe before cutting, does the manifold to cat gasket need to be replaced since he pulled it apart?
BONUS QUESTION: Easy way to add diff fluid without a lift?
Thanks LS1tech, hopefully ive given enough information
03-04-2010, 05:46 PM
#3
i dont think this is your problem, but when i put headers and full exhaust on i was told it may make my car smoke more as it makes leaky exhaust valves more evident, maybe the extra exhaust flow is allowing you to hear something you couldnt before..
03-07-2010, 02:42 PM
#6
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if you can only hear it through the exhaust i would say its something thats always been there you just couldnt hear it before... i would def put a new gasket in that flange as well, that could def be a prob... at lower rpm theres not enough exhaust, and at higher rpm it flows past the leak, id put my money on that being your problem
as for adding fluid, jsut put a jack under the rear and chock the front tires, make sure you can add fluid before letting any out.. very simple
as for adding fluid, jsut put a jack under the rear and chock the front tires, make sure you can add fluid before letting any out.. very simple
