piusthedrgolf

I got CEL on.
I checked it and gave me "Main Catalyst Efficiency Below Threshold (Bank 2)" from scanner on 02 E320 4Matic Wagon. I searched the forum and found few interesting posts and have few questions.

1. Which side is Bank 2?

Replacing them with Magnaflow 53005 - Magnaflow Universal Catalytic Converters

1. How do O2 sensors get attached on those universal cat?
2. Will it make CEL be turned off?
3. If I chose to do with Universal Cat, Do I need to replace the other side also?

Thanks in Advance

RichardM98

Bank 2 is the left side as seen from sitting behind the steering wheel (driver's position)

O2 sensors are located in the exhaust header before or beyond the catalytic convertor. Cat failures are often due to faulty MAF sensor. Rich fuel mixture causes overheating and meltdown!

The CEL will go off automatically. However, there may be a 'pending' error code which can be cleared by using an inexpensive OBD II scanner or auto shop may do it as part of installation.

Do both? Hard to say. If you have high mileage then probably since both have seen the same amount of use. If low mileage then maybe one not made as well as the other. If in California, be sure to get CARB approved ones.

piusthedrgolf

First, Thank you for your reply. Few more questions follow.

If it was due to faulty Mass Air Flow sensor, wouldn't it be shown in scanner? How do I check if it is bad or not?

Do I need to change O2 sensor if I decided to go with Universal cat?

RichardM98

The MAF provides an electrical signal which varies according to air flow. A faulty MAF still provides a signal but not an accurate one so the air:fuel ratio is wrong -- usually too rich.

I once saw a detailed test protocol for the BOSCH MAF's but it is way beyond the average DIYers equipment and skillset. MAF's last about 100K and cost about $100 so I think most people just replace it if there is an issue.

You didn't say if you have a OBD II scanner. If you do, then I would suggest scanning the car every so often to look for codes common to the MAF or O2 sensors. If you don't you might consider getting one if you are inclined to do you own testing. Sometimes codes are temporary and after clearing them they don't come back.

ohlord

you have is for the primary cat located between both pre and post o2 sensors on the drivers side of the engine.
The universal cat you are looking to buy is the secondary cat. Wrong item.
Look at the diy section on w210 forum www.benzworld.org
for model of universal primary cat.
Where are you located?

piusthedrgolf

I'm in 22030, Fairfax, VA. I searched 'DIY' in W210 Forum but I don't see any thread that discuss model of universal primary cat. Would you please provide the direct link? Thanks.

piusthedrgolf

Don't bother. I found the thread, http://www.benzworld.org/forums/w210...converter.html .

According to you, Where do I find right universal cat. for mine? I use AutoHausAZ but they don't carry universal cat. Would you recommend any online shop for these parts? Thanks.

IZZY2000

I have an 00 E320 mine went bad 3 months after i bought the car. I went to this local place here in TAMPA FL and paid 192.00 to change it from 2007 in till today i have had no problems. Mine was the passanger side catalyc. The place where i took it to was RAINBOW MUFFLERS. Check the sensor located by the AIR filter that goes inside the plastic tube that went bad at first on mine i change it i bought that Sensor in ebay for 92.00.