Catalytic converter rattling on 2.7l 1996?

Is it possible for it to hurt the fuel mileage by taking this off and busting all the charcoal out of it and putting it back on.I know it turned on my check engine light?

 

There is no charcoal in a cat.
I suggest replacing with a Magna Flow replacement.

Good luck.

 

Yeah if it's rattling most likely the internals have come loose. That happened on the flowmaster cat in less than a year. My magnaflow has lasted twice that and then some.

 

if your catalytic converter is rattling, it means the catalyst element is shot. If you gut your cat converter and put it back this wil trigger a check engine code because of the o2 sensor detecting the emissions as unfiltered. It may or may not cause bad gas mileage, depending if the truck wants to think it's running lean/rich or not.

There is a way to trick the sensor but it's just better if you put a new catalytic converter back on. Don,t need to be genuine OEM. Aftermarket will do but don't get the most cheapie-cheapo either because they don't last

 

Make sure it's not the shield above the cat that's making the noise. Common issue.

 

I agree with the above ^^

forgot to mention it, but yeah, before throwing parts at the truck, check for this first. Would suck to spend $$$ on parts just to find out it was the heat shield

 

Thanks for the back up. I've had the dreaded P0420 code 3 times in past 5 years, plus the rattling. Haven't had to replace the cats yet. Exhaust leak at flange upstream. A/F sensor B1S1. Exhaust leak at Ypipe donut.

 

I recommend Toyota cats if you have pockets lined with gold...nothing beats OEM quality especially when it comes to cats

For aftermarket, Magnaflow is the next best thing