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Used Catalytic Converter safe?

Recently I had my check engine light come on in my car as well as a service light. My car is at 140,000 miles and I drive it around the county for work so I knew I would have some expensive repairs in my future. My stepdad disconnected my car battery and then reconnected it which caused the light to go out so my mechanic was not able to read the code to find the issue. (We did find that my service light was coming on right before my headlight went out so I replaced the bulb and have not had the service light come back on since.)

My mechanic let me know my catalytic converter pipe was rusting and falling on my exhaust and gave me an estimate for the cost of a new pipe, O2 sensor and labor charge. He quoted the catalytic converter pipe at $304.25 and with everything else involved, the total for my estimate came to $521.00.

I have read before that some people suggested possibly finding a used pipe at a salvage yard to save money on the repair. I called around and found a place that would sell it to me for around $100.00. I’m not handy with cars and know the bare minimum when it comes to repairs, so what I don’t know is if it is safe to use a pipe from a salvage yard compared to buying a new one. Is anyone able to let me know whether it is a good idea to save a couple hundred dollars and use the old pipe or if it is better to be safe than sorry and replace it with a new one?

How long do you plan to keep this car? Your mechanic will have to give you a guess on how much life is left in the junkyard pipe, which may not be much. I’d hate to pay for labor a second time if this one fails while you still have the car.

I had thought about getting another used car but I’m a strong believer in making a car last as long as you can without paying over the worth of the car. I’m hoping to drive it as long as I can without repairs costing over what I would pay for car payments. I’ve asked him before if he was able to give me any kind of estimate as to whether I will be looking at a lot of repairs in the future but obviously he’s not able to predict what will happen. He just said he’s driven Cavaliers that have lasted longer than 200,000 miles so it’s possible mine may last a good bit longer. But I understand your concern, it may be better for me to simply pay more for a new one so I can be sure I won’t have to fix the problem again in the near future.

Not sure whether this is state wide but here it is illegal to sell used cats.
If it is illegal in your state, it means your mechanic is a bit shady. Just beware.

Thanks for the heads up! I did not know that. I’m not sure if it’s illegal in Ohio but I’m guessing if it’s illegal in other states it may not be the best idea for my car.

Is YOUR car a Chevalier? What year and engine size? Since the CEL has not returned, thank your step-dad and drive on…Today, most cars use a stainless steel exhaust system that lasts a long time…It’s illegal for junk yards to sell catalytic converters…

Well, just google it. I do know that Ebay does not let you sell cats so suspect it is federal law.
Depending on the car, you can get aftermarket CATs for much cheaper and have them work well.

Edit: What year and make is your car? CATs do go but am wondering whether you even have a bad CAT…

Yes, my car is a 2002 Cavalier with a 2.2 engine. From this info, I’ll most likely be paying for the new one. I appreciate the help!

It’s against EPA regulations for a salvage yard to sell used catalytic converters. If caught, the fines can be as high as $20,000 for each used catalytic converter sold.

Tester

Now I’m confused. Do you need an exhaust pipe or a catalytic converter? I assumed you just meant an exhaust pipe.

I assumed “converter” as that’s what it said in the title.

If the car is not making noise I would leave it alone for now. Exhaust pipe especially towards the front of the motor is strong stuff. It may take it years to actually rust all the way through…

Yes its Illegal to sell used cat converters… With that said, your used one (assuming its OEM) is worth $100+ just for scrap at most recyclers. There is a bunch of precious metal in there. Most exhaust shops don’t tell you that, and I have heard stories about shops saying the cat is bad so they A) get to sell you a new one B) scrap the old one. So watch out !!

She was pretty clear in the post that it was the pipe, and based on the cost she was quoted I’m convinced.

IMHO replacing a rusted pipe with a boneyard ippe is just a very temporary bandaid at best.

Sorry for the confusion, I was trying to give a little background info about the repair. I need my catalytic converter pipe (reading what my repair estimate says) replaced. I do not need a new exhaust pipe.

So the pipe leading into our out of the cat? Yeah, those can be bought second hand as that’s just a pipe - of course, a second hand pipe could still be rusted.

Ok thank you for such a quick response!

Good luck with it.

It’s never safe to ASSume ANYTHING here…

You might look into a universal catalytic converter. The old converter is cut out and a new one welded in it’s place, usually lots cheaper than a direct fit converter. Yes, it is against federal law to sell used catalytic converters for any other purpose than scrap metal.

Never knew used cats were illegal to sell.

I damaged the exhaust on a Subaru WRX. I ended up buying someone’s entire cat back stock exhaust system($300) they pulled for performance reasons at 15k miles.