Cat Died Prematurely
 

Had an aftermarket cat installed a month ago. Had it inspected yesterday and cat suspected to be dead by the rattling noise inside it.

Techie says it may be caused by rich mixture of air/fuel ratio. Is this true?
My mix is 50%, and car passed emission testing.

Aftermarket cats are just THAT..aftermarket. No real quality control.

Many aftermarket cats are too small.

You don't specify which car model?

Aftermarket cats on a Benz, esp. a newer model, are a big no-no. Quality and performance are major issues. There is a reason OE cats cost $800+ a side. Materials, (semi) precious metals, ceramics, etc.

Aftermarket cats can also affect emissions, depending on the car.

All IMHO. ;)

It is a 89 260E with originally 2 pre cats. The replacement is just twin pipes from the exhaust manifold.

But the cat being destroyed in two weeks is just insane!!!

Did you idle the engine for a good 30 minutes, and drive carefully for the first few hours, to allow the new cat to bed in?

The rattle is the honey comb material haven broken lose from the wall of the cat some Friend of mine had the same thing happen to his, He just ran a few long sheet metal screws threw the wall of the cat to stop the rattle, NOT the proper fix but if you did not buy the proper one first, this may give you time to save up for the correct unit

No, but is it bad enough to destroy it?

The cat may have been damaged during shipping, during installation, who knows? It could just be a very cheap, crap-built aftermarket cat.

If the rattle isn't too bad, you can also try crimping the cat slightly with a large set of pliers or a C-clamp. That can help get rid of the rattle for a while. Emissions and performance are a whole other issue though.

If you plan on keeping the car and want to keep it running well, I'd bite the bullet and purchase an MB (OE) cat.

Yes, it is entirely possible. I had this happen to my 87 Ford F-150, Bigfoot Cruiser 4x4 truck. It turned out to be the fuel pressure regulator, which caused the problem. It kept more or less, flooding the engine, and as a result, fried the two catyletic converters, and the two O2 sensors..

It's only got that crappy 302 in it. The thing has two cats, one right in front of the other, on the same pipe, under the passenger floor. Since it is all one piece, with the Y-pipe, it will all need to be replaced. I got a price of $1500.oo for the front Y-pipe assembly, with two cats, and two O2 sensors on it. The truck is barely even worth that much to begin with. Realistically, the only thing which gives the truck any real value, is the fact that it's an original Bigfoot Cruiser edition. Got some really cool options, Like power, up/down rear cab window, roll bar, factory lift kit, and 35" tires,XLT Lariat, and a bunch more other things...but I'm still hesitant, and keep procrastinating putting any money into it. Aside from mechanical ailments, the truck is flawless, so for now it is just holding down the floor in my warehouse, with a lot of the rest of my vehicles. Nice paper weight, because it won't even stay running long enough to get it out into the sunlight, in one shot. Ever have a Potato clog your exhaust system..? It's giving the same effect...

Is the car burning oil ? If there is excessive oil burning, it does not take long to clog the CAT up. Maybe the CAT overheated as a result and parts inside just cracked.

That's friggin funny!!! Sheet metal screws into the cat...

Did the guy put duct tape on his dash board cracks, too?

I know a guy who does that sorta stuff to his vehicles all the time. He had a 69 Chevelle. The rear quarter panels were so rotted out that he took cardboard, and duct tape, and actually constructed new sections for the car, and paineted them to match afterwards. There was Duct tape everywhere on that poor car. Inside, outside, even the floor boards fell victim to the tape, and carboard treatment. He was nowhere near hard up for cash either. He just took great sentiment in the car, because it had been his mom's car, before she died, and she left it to him.

We used to call it the "Duct tape mobile". He was a friend of mines dad, so we used to tease him about it sometimes...The good old days...HHMMM.

OEM cats are twice the price of the car.

Unfortunately that's not really true. The cost of the cats are driven by those items, but the total cost is much, much lower than what you pay. The price the customer pays is determined by what GSP (Global Service and Parts) thinks the market will bear plus the exorbitant markup charged by your stealership.

[QUOTE=Hirnbeiss;1548603]$3770 in my case. This HAS to be a joke within M-B. No I didn't buy it.

The quote I got was from my tech, his actual cost before any markup.

The main cat on my 300E lasted over 300,000 Kms. Don't think an aftermarket would have done as well.

Not saying they aren't overpriced, but you get what you pay for in any case.