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Discussion Starter · #1 · (Edited)
100,000 miles on the car - at about 65-70K, I put a couple of tankfuls of high octane "leaded" gas in the car mistakenly.

Well, after a few SES lights shortly thereafter indicating cat, O2 and other faults and a head replacement, no more SES lights.

About 1k ago, I replaced all four O2 sensors for the 1st time and my tech told me that he had never seen O2's like that and I reminded him of the leaded gas and he said that was the probable cause.

When he replaced the O2's, he also put it on the computer and said that he saw a cat fault that had not registered yet on the SES light.

He said that it was likely caused by the bad O2's but after 100,000 miles and the leaded gas issue, he said that he obviously couldn't be sure.

Now, as I start the car, I get that rotten egg smell that I never had before and the car is running very slightly rough at around 3K rpms but, no SES light (yet).

I made an earlier post on a very slight "ticking" noise but now, I have to believe that it's the cats.

Please give me some suggestions on where to get the cheapest OEM cats and a ballpark on what they will cost along with the install.

I'm thinking around $2500 for each cat plus installation - is that about right?

Thanks
 

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I just got one of my cats replaced, it was under warranty however, and the bill came to something like 2400 installed, but then said no carge , since it was covered under warranty, however when my cat went bad it kept througing SES ligts and the codes were cat inefficiency, as far as drivability, I experienced a decrease in power, some hesitation and a tonal change of the exhaust, and it became noticably louder inside the car with the sound coming from the transmission area, which in retrospect makes since since this is near where the cats are, however maybe my experiance was/is different then yours since maybe cats can fail in different manners? hope this helps and good luck getting it fixed, Josh
 

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have you considered aftermarket cats? i believe evosport sells some that are about 1/10th the estimate you mention.
Mike
 

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tranck said:
Tell me more - I see the advantage - what are the disadvantages - if any?
I don't know too much about them, but remember a discussion about aftermarket cats a while back on the board. The superspring race cats (which are around 2500 for the set, i believe) will occasionally trigger a cat efficiency code and an ses light. Evosport had said these cats that they use have had no issues.

Only downside i'd see is needing to weld them in place of the stock cats. I don't know what they look like, so if you have to pass a visual smog inspection, they may look suspicious. Certainly worth a call to them, the $250ish price was from my memory, which is often way off base!
Mike
 

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Another symptom from clogged cats is the bank leaning out.
I showed lean out codes when mine clogged.
I thought I needed a new O2 sensor till I sled under for a look, thats when I heard the rattle. I knew I should have looked at that before the 80,000mile mark.
Opting for the betterflow is a great way to go as it helps the accelleration.:M5rev:
I spent about the same amount for both, then welded them in one weekend.
 
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