98 280 Catalytic Repair

[jswong888]

Hi,

I have a 98 c280 110K miles. The catalytic converter is busted as it is rattling for 3K miles now and causing the CEL to go on.

I want to replace it but do not want to spend alot of money going through the dealer. I'v been searching on this forum, so far, my options seem to be:

1) repair the cat, hopfuelly this will get me some more mileage out of it.

2) get a non-oem replacement. Dynatech or Magnaflow? is this correct, but could someone tell me what the specs or model #'s are ( in terms of sizes of the inlet & outlet)

3) get a dealer replacement (would like to avoid).

Any help is greatly appreciated from this forum.

[Ashkan's C280]

supersprint has some high flow cats, that would be better than OEM, correct me if i'm wrong, evosports site should have it

[manny]

Option # 2 is by far your best bet.
Talk to " CKlasse" in this forum.
He will fix you up, I'm sure. ;)

[CKlasse]

I can rebuild your stock ones.. depending on where you are located, we can use 2 layer (higher flow) instead of stock 3 layer setup.

[Ashkan's C280]

hey ck, send me an email please, I had a few questions to ask...

[jswong888]

Cklass, I'm located in SF bay area. Can you still repair. Looks like the cat is welded on (not a bolt on). need I goto muffler shop top take off and send it to you? or am I better off just getting the magnaflow or dynatech and have a muffler shop to install it?

Thanks

[CKlasse]

Before you replace/repair your CAT, you need to find out the CAUSE of the damage.

Some of the common problems:

Too rich/lean AFR mixture
Oil or cooland leak in the cylinder
Excessive heat (Mostly Chrysler/Jeep)
Physical Damage

You will need to fix your mixture or cylinder (gasket) leak issues before replacing the cats. These CATs are under warranty for 5 years against any manufacturer defects, but not against the engine itself.

CARB requires ULEV rating on most MB. This means your option is down to 'rebuilt unit' only. If you insist on HI FLOW cats, I cannot warranty anything. You will pass emission, the result is right on the 'border.'

Stock cats usually yield 2psi-4psi.
Rebuilt cats (400 c per sq inch) produces 1-3psi.
Hi Flow cats (200-400 c per sq inch) products 0psi of backpressure upto certain CFM..
e.g. 2.5" Hi Flow starts to have backpressure (.5 psi) at 300 CFM.

POST any questions here, so the rest of the forums can read them.

Thanks
Ken

[jswong888]

Thank Cklass for the Insights.

The problem i suspect has to be either:

1) physical damage. perhaps i ran over something on the road.

2) or the air fuel mixture.

I highly doubt that it's a leak of oil or coolant in the cylinder as the levels on them are normal plus the engine runs STRONG...

By the way, i'm not too concerned about warranty. the car is 7 years old with 110K miles on it. Im just looking to get the problem fix and continue running well.

Also, considering there's a lot of MAF issues with MB, is it not unusual that the cat is shot ny now (plus dont they go out at about 100K anyways?).

What is the process and cost to get the cat repaired?

Thanks again

[714guy]

Ken What your info again?? i would like to get a hi-flow cat. i lost all of my contacts.

and got a few question abour my rice exhuast i have.

Thanks

[CKlasse]

ken@budsmuffler.com

or

303 629 0934

Guys,

I got a couple shows to attend this weekend. So I have been real busy preparing the booths. Sorry I havent gotten in touch, feel free to call me at that number, or email me!

Thanks
Ken