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300E Bad Cat Converter ?

Hi

I just had my emissions / smog check here in California and the NOx were really high. Very close to failing.

I suspect a bad cat. I measure the temp of the cat with a fluke infrared and measured 245C or 473F. The temperature was the same at the front, middle and back of the cat. The car was running at operating temp, I did this after I came home from work and the water temp was near 100C

Shouldn't the reading be closer to 426C or 800F?

Ideas? It looks like the original cat , the car has 175,000 miles

Reply to
Tube Audio
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You got your monies worth out of that cat. You need a new one.

Do NOT just weld in a tiny POS cheapo cat. Get a real one WITH the pre-cat. Like this one:

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Reply to
Karl

thanks for the reply, at first I thought you meant buy a new car. :')

I live in California but the car is from the east coast, so I should NOT get the California CAT?

how about the catco for $255?

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Reply to
Tube Audio

Not so fast mit der schpending off der big bucks Check the EGR valve, either clean or replace, also vacuum lines Peter

Reply to
Peter W. Peternouschek

Why do I not see a cat in that exhaust?? Why does that so-called cat not look like any USA exhaust??

Open your hood and look down where the exhaust bolts to the exhaust manifold. Do you see pre-cats there?

Go here and look at the lower exhaust in the picture. That is what you should have.

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Reply to
Karl

You would be surprised at how little a EGR valve lowers NoX. EGR lowers combustion temps to stop the formation of NoX. NoX forms when combustion temps exceed 2500 F.

The cat controls about 95% of NoX.

Reply to
Karl

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