P0422

[vaspen]

P0422 main capitalist efficiency bank 1 below threshold is what our modis is saying any advice because when I look it up I get the actuator valve for the s.c ? New lower o2 and new cat upper 02 is older

[RemoLexi]

You need a new cat. There's nothing much to dig into with a cat efficiency code.

[vaspen]

It's a brand new heavy duty cat .. that's the thing tho

[vaspen]

Now I should state on my way home when this occurred I was putting along at virtually 1200 rpm the whole way so Maby it's just a flook that my exhaust just didn't get to temp because of the 3inch pipes

[Vetruck]

How old is new? Some of the non-compliant cats can go bad in a year or less. They do not have as much of the good stuff in them and burn up pretty quickly- once this happens, there is no heat build-up inside to burn off hydrocarbons and render a different reading on the trailing O2 sensor from the leading one.

[vaspen]

Maby 4-5 months ? I got one that was strong enough for 8000pnd limit? Around there

[vaspen]

http://www.jegs.com/webapp/wcs/stores/servlet/m20ProductDisplayView?pageSize=10&resultCatEntryType=&searchTerm=&catalogId=10002&langId=-1&productId=2073622&storeId=10001&sType=&pgGrp=search
close to this I know I made shure to order a heavy metal cat for longevity

[Vetruck]

The Calif Compliant cats have the platinum and lots of it. I would not trust others. That is the reason we have more strict laws here in Calif- we can not use the other ones because they do not work well enough for our emissions testing.

[vaspen]

I hear ya there but heavy metal to ceramic I chose the heavy metal (wont melt like ceramic will )
I really think its just my upper o2 sensor like I stated I redid the cat and lower o2
plus that day I was going super slow so I really do think my exhaust just didn't get hot enough
it was wet out also and lowered ..lol
as soon as I pay my 77 t.a off ill snoop around on it

[vaspen]

Ok after some reading I will take our modus and test both o2 sensors before any conclusions no way my cat should be bad or I'm going to call magnaflow it's only been Maby 10k tops ...

[RemoLexi]

This is the thing- you install something that you are soo stuck believing is perfect, and you start fiddling with the rest of the car looking at something else to blame. It's your cat. Keep it simple.

The aftermarket cats don't last at all. I see it all day long 'well I just put a cat in last year?!' That's what you get for $300.

You are replacing an already known piece of shit part that Mercedes couldn't make last over 100k with an aftermarket bigger piece of shit part.

[vaspen]

Well went for a drive after clearing codes spanked it and drove sensible on the way back but not as slow or low reving as the day the code came on ..
no cel light but my tires are shot so it's parked untill New rubber comes do do further testing

[W202FTW]

Never had to replace any of the factory cats on any of the 202s and 210 that I've own.

Key thing is to scan for PENDING related codes and emission monitors with a good scan tool after a good drive cycle. Also, don't carpet bomb your car with cheap parts.

[vaspen]

Still hasent came back on I'm going to drive the 500 miles the ecu requires by state emissions these are not "junkparts" that are on the car like I stated I believe that the upstream o2 that is what rolled of the factory lot is going bad my father has been doing exhaust jobs 25+ years and rarely sees a magnaflow cat go bad that quick