You know, when the only tool in your toolbox is a hammer, everything starts looking like a nail!
I have been gritting my teeth and enduring some nasty buzzing at low RPM's from the passenger side of my exhaust system for something like five months. It's bad when the motor is cold. However, after it's up to temp, it was undetectable until I drove the car down my alley and could hear a slight buzz or rattle as I pulled into my garage.
I was under the car a while back and all the heat shields are tightly screwed down and not the culprit.
So, having Good Friday off and the wife out of the house doing errands in the other car, I decided to jack up the car in the garage, fire up the engine, locate that buzzing rattle and do something about it.
The culprit? It's a steel heat shield that goes around the exhaust pipe leading into the cat, about seven inches long with tabs on each end (for removal, I guess).
Banged it a couple of times real good with a hammer to tighten it up, and took it for a test drive. Ahhhh, no more buzzing or rattle!
Who says one should never take a hammer to their car when frustrated with a nagging problem?