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Possible Exhaust Issue on Impala?

My 2003 Impala has been running fine for months now, after about 6 months or more it got exhaust work and 2 months ago it had to get exhaust work again.

The muffler actually fell off on a long drive and a garage nearby said the previous garage totally screwed it up because the said the exhaust pipe was cut too short and they had to weld together a “fixer piece”.

Then we took it to our local Firestone simply to get the hubcap covers taken off as it was a free service and after we had to them put back on, about 1 day later, we started getting a strange noise.

Everything sounds fine when you are idling yet the minute you start moving and especially with all the windows up it sounds like somebody is running a lawn mover or an airplane is flying above.

There is no vibration or anything just that strange noise.

What kind of shape is the catalytic converter in? I recall when mine failed (due to 02 sensor failure and overly rich fuel) the plates melted and collapsed and the exhaust rattled and resonated something fierce under load at lower speeds.

“Then we took it to our local Firestone simply to get the hubcap covers taken off as it was a free service and after we had to them put back on, about 1 day later, we started getting a strange noise”

So if I understand correctly, his noise started the day after you had the hubcaps removed and reinstalled? What all did the Firestone place do, anyway? I can’t imagine somebody going to a tire store just to get their hubcaps removed and replaced.

Then we took it to our local Firestone simply to get the hubcap covers taken off as it was a free service and after we had to them put back on, about 1 day later, we started getting a strange noise.

@Reddie: I’m as puzzled by this as Mountainbike. It’s pretty hard to guess what connection you are making between the hubcaps, the pre-existing exhaust problem, and the noise after the hubcap work (?) was done. Can you explain what the hubcap removal was all about, and how that might be relevant to the exhaust situation? Did Firestone do any work on your exhaust system? Did they put your car on a lift for any reason? It sounds like you may have an exhaust issue, but judging by your description of the noise it could be a lot of things, ALL of them unrelated to hubcaps.

Try this. Get someone to sit in the car with the engine running, parking brake firmly set, and car in park, while someone else gets down on the ground beside the car to listen to the sounds. Have the “driver” rev the engine slightly. Do you hear the sound you described as like a lawn mower or airplane? Does the sound come from under the car? Or is it up front? Is it a sort of vibration noise, or more of a engine sound - popping - like an opening in the exhaust pipe. Post back what you find.

Firestone will remove your hubcaps without charge, but the fee for reinstalling them is really excessive!
;-))

Seriously, however, I am also waiting with bated breath to find out why the OP wanted to have his/her hubcaps removed and reinstalled. In any event, the hubcap scenario is unlikely to be related to this noise problem unless some type of service–beyond hubcap removal–was performed.

We really need more information from the OP.

I am stumped too about the hubcaps. I do think I mite have an answer. Could it be they used a floor jack to lift the car and missed. IE lifted the car with the exhaust between the jack and the car.

@oldbodyman: That’s what I was wondering about, which is why I asked if the car had been on a lift…a floor jack could easily cause damage too, as you explained. But why would they need to jack up the vehicle to get the hubcaps off?

I sure hope the OP shows up to explain this. It feels like we’re chasing our tails on this one.