Rattling when accelerating

[ChrisTheBest]

for some time now, when im accelerating i hear a rattling under my car. and when i push it harder the sound gets louder. I took it to a mechanic and he told me to put fuel injector cleaner in it... which did nothing for me. any one have similar problem's as this and maybe a solution? thanks

 

[Jim Henderson]

without hearing the sound it could be anything.

But a few guesses. Rattling or buzzing that varies with engine speed is often from loose exhaust shields, hangers or connections.

I recommend crawling around under the car and grabbign and shking anything you can get your hands on. Feel around exhaust pipes for sheet metal shields that often come loose. Check the exhaust hangers to make sure they are tight and haven't slipped off their body mounts.

Other things that rattle can include loose pulleys or engine covers or splash shields.

Your mechanic telling you to put in injector cleaner makes me suspect that the sound might be more like engine ping or knock, a rattle would be a bad knock. This can happen from hot weather, heavy loads, inadequate gas octane or an engine that is mistimed or has deposits.

Good luck,

Jim Henderson

 

[absentee]

its likely the exhaust. either a broken shield on the cats, the cats themselves broken up inside, or a o2 sensor loose (really, I had that happen on my old tbird, a loose o2 sensor was rattling around and sounded just like a broken up cat)

 

[ChrisTheBest]

good idea, that makes sense. im planning on putting some magna flows on at some point. when i have a opportunity im going to inspect the heat shield and cats my self.

 

[Gus_Mahn]

What grade fuel are you running? My '01 LS8 has lots of tip in detonation ( as you step on the gas to increase engine speed) on cheap fuel. Because of this, the car gets 93 octane every tank.

 

[The Hotness]

Yes, you better be putting premium fuel in this. I am willing to bet when driving up a hill and you punch it, it is extremely loud. If you feel that you are hurting the car, you are.

Premium fuel, premium fuel. If this doesn't fix the issue, then you likely need the injectors cleaned, new fuel filter, and some new plugs wont hurt.


EDIT: Your sig says your tuned, flash back to stock for the time being as well. Just my recommendation.

 

[pagluy]

Go back to stock tune and tell us if it still does it, ook?