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I was driving to work one morning with CEL on and was cruising at 60mph when suddenly the car lost power. I stepped on the accelerator and nothing happened. I pulled over and the car was idling very rough. The CEL was blinking. I had the car towed home and I checked the codes. PO156, PO161, P
O304, PO306. PO300. I replaced the O2 sensor 2 Bank2, and all 12 sparkplugs, cleaned the MAF sensor and erased all codes. I started the car and still the same problem. CEL is blinking and the codes are PO304, PO306, PO305 and PO300. The car idles roughly and when I stepped on the accelerator it almost stalls. My car has about 173,000 miles on it. Anyway, based on some previous postings it looks like I have a fried cat at bank2. Any ideas, comments or suggestions? Thanks!!!
 

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the codes again.Drive it and then check the active codes and the pending stored codes.Then run the car at idle for 15minutes and with a non contact infrared thermometer check the temp of the pipes for and aft of the bank 1 cat and then for and aft the bank2 cat,bank 1 is pass side bank 2 is drivers side.If you are in the USA.fill in your profile:D
compare the temps that will be the surefire test for cat failure.Or when cold give it a thump with your palm and listen for the guts to bounce around.
Get a mechanics stethoscope and listen to the injectors on bank 2 compare them to bank 1 to rule out a fuel rail problem.
universal cats about 60 bucks at racepages.com any good custom muffler shop can splice them in for you.If that is what the problem turns out to be.
:bowdown:eek:hlord
 

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Thanks Ohlord!

Cleared the codes and started the car. Can't drive car around cause everytime I floor the pedal, the engine almost stalls. Same codes came up-P0304, P0306, P0306 and P0300 respectively. Let the car idle for at least half an hour and listened to the injectors on both banks with a mechanical stethoscope and all sound pretty much the same. Then I measure the temperature of both cats. The reading are as follows: Bank 1=406'C before 417'C after. Bank 2= 307'C before 331'C after. I also notice a jingling sound coming from the Bank 2 cat. Does these reading point to a bad bank 2 cat? Anyway, please interpret these readings for me. By the way, I'm in South San Francisco,CA.
 

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you get under it again and with the cat cool to the touch give it a wonk with the palm of you hand a few times so you can listen if the guts bounce around?From the temps it looks like it is so plugged the whole bank 2 (drivers side)is not firing properly.And by the sound you describe,that may confirm it.In california I am not sure how they examine non ca approved cats.So you may need to call a custom muffler shop to see if they can splice in the cats from racepages.com or call them and see if they sell ca approved cats.Not being there to examine it myself it really does indicate the cat.However,something may have caused the cat to fail and you really need to get it on a scope at an indie shop,1 to confirm the plugged cat and 2 why it failed.Sorry it sounds like money but a few bucks tracking down and confirming the why,will save a lot of money if it prevents another cat from frying.
:bowdown:
these guys from what i have heard do nice work at diagnosis and have fair prices for service
Mercedes Benz Service Connection Mobile A or B, Not from the Dealership, but Mercedes Benz Mobile service from The Workshop Mercedes Benz Mobile Service, for service A,B,C,D,E,F,G:,H in vehicle models C,E,S,SL,SLK,SL,CL,CLS,CLK,G,GL,R,and ML classes
 

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I found muffler shop in San Francisco that replaced all my cats or $500. The CEL or codes has not come on. The car runs really really well. Hopefully, that fixed the problem. Will keep you posted if anything comes up. Thanks again Ohlord!!!
 

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Thanks for the update,it slipped by me:)
Did they install universal oe from racepages.com or did they have another source?
anyone searching this thread in the future non contact infrareds are cheap at harborfreight tools and an easy test of cat function.His was so plugged up it was strangling the whole bank of the engine.People start throwing in hundreds of dollars of coils and plugs and wires and injectors and a simple temp or thump test might have shown them the Op's simple solution.
:bowdown:eek:hlord
 

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I bought cats online but the local mufflershop refused to install them because they don't have OBD2 compliant stamp on them. So I called other shops whichwere qouting me anywhere from $320 and up for the front cat and $280 and up for the rear. Then I came across this shop in San Francisco "Discount Muffler shop" who quoted me $180 for the front and $90 for the rear installed. Then the owner said that since all four cats were shot, all were rattling when he hit them with his palm, he said that he'll replace all of them for $500. He installed aftermarket OBD2 compliant which he has in stock. The car been running well ever since.
 
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