Exhaust Rattle, Running Warm, & Dented Cat

[Nick1994]

I might be asking the obvious here. Lately I've had an exhaust rattle with the Jeep. It's a bit louder, only at idle. Any bit of higher RPMs makes the sound go away. When it's making the sound, I've crawled underneath and it makes the sound somewhere around between the catalytic converter and the muffler. The catalytic converter has some fair sized dents in it from taking it off-road. Not sure when it happened. Could have been a year or two ago. All the hangers look fine and it isn't rubbing on anything.

Also, out in the desert when driving in 4x4 in the sand it was getting up to about 220 degrees. The entire cooling system is new. Also in traffic yesterday it was getting up to 220 degrees. Out on the highway it's at 200.

My guess is some honeycombs in the catalytic converter have broken, making it run warmer in traffic and rattling. It's got plenty of power, no issues there.

So I'm guessing it's time for a catalytic converter? Anybody have any recommendations as far as brands? Magnaflow has one for $125 on Amazon. My Jeep has an O2 sensor in the back of the catalytic converter.

Thanks for any help

 

[RooflessVW]

I would just let the shop that's doing the replacing provide the converter. One stop shop.

I have also had good luck with Summit Racing's house brand exhaust components.

 

[Black_Thunder]

before you go spending that kind of money.


try taking two worm clamps like coolant hose clamps obviously bigger ones or 2 that can be connected together and put them around the cat shielding and tighten them up and see if the noise goes away



I've had loose shields start to rattle and make noise at idle.


I've also had an O2 sensor loosen up and cause a rattle that made it sound like a shield was loose.


i don't think it would cause an overheating issue especially if its running fine with no power loss issues.


I know you said the cooling system is new, but couldn't hurt to blow out the radiator and check the fan.

is the thermostat new as well?

 

[Lubener]

Looks to me to be just a dented shield. If you had an exheaust blockage from the cat's inners, power would be way down. I had that and the car struggled to go up a hill. A vacuum gauge would verify an exhaust restriction.

 

[LeakySeals]

Shove a screwdriver in that gap between the pipe and the shield. Bend it back. See what happens.

 

[spk2000]

It's likely the heat shield. have had many of those rattle especially on Ford's. They use bands instead of welding them like everyone else. The large hose clamps should help if it is the heat shield. Or tear it off.