Clogged up my 3rd magnaflow cat

98LSC32V

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I put a full bottle of techron in the tank and only filled up 6 gallons, driving down the freeway and the car starts bucking and died on me... figured out I clogged the 3rd cat, opened up the cut outs and it runs fine... I know it says to fill up a whole tank but i'm still staying away from using that stuff anymore...
 
I'm pretty sure the '3 cat' on Gen 2's is actually a resonator and not a cat. Any modern car that has cats has o2 sensors before and after to measure that the cat is working. I could be mistaken but I doubt it.
 
actually that is a catalytic converter:cool:yes you are wrong, doubt im not.
 
I will get under my car tomorrow but I am 99% sure the rear O2s are before the resonator. Also according to the new service manual I have the car onlyhas two convertors and has no name for that resonator.
But if it does not have O2s after it then it is not a convertor. They have to be monitored.
If it was a convertor then when people install the x pipe they would get a CEL. I havent run across one of those threads yet here.
 
No, just because it doesnt have 02 sensors after it does not mean it is not a cat. On the passenger side of the car the first cat is part of the pipe on the driver side it is part of the manifold. Any post OBD2 car [96 and newer] has a catalyst efficency o2 sensor after the first set of cats. Now fomoco does call this a resonator, but it has all the precious metals a cat does and if you go to replace this part you will Know in the wallet that it is a cat for sure. I sell alot of the cats that I remove to an old deaf guy that extracts the metals himself. He pays for these like anyother cat made. THIS IS A CAT! :D
 
the third cat is a "NOX scrubber".. it is most definately a convertor
 
When I had the SQ and had to have the exhaust redone, my exhaust shop was able to remove the center resonator and replaced it with a double X because the manuals said he could but they cant touch the cats. Then it might be a resonator / scrubber on gen 2's (I dont know Gen1's)
 
On my 95 first gen, the third cat IS a cat.. a nox scrubber.
downstream from that IS a resonator which can be removed.

The cats and the NOX scrubber should not be removed on an engine that is to remain emissions compliant.
FIRST OR SECOND gen matters not.
 
+1 XL I have been saying this the whole time but what do I know I only work at car x. rattle rattle thunder clatter boom boom boom...........:shifty: And also the exhaust shop that did that work for you probably made about 75 bucks off youre converter that they "threw away" for you Phreak.:eek:
 
On my 95 first gen, the third cat IS a cat.. a nox scrubber.
downstream from that IS a resonator which can be removed.

The cats and the NOX scrubber should not be removed on an engine that is to remain emissions compliant.
FIRST OR SECOND gen matters not.


+1

Tommy is right. The monitor o2s are after the first set of cats so the third cat is not monitors and therefore will not through a CEL is removed but that still doesn't change the fact it acts as a cat.
 
I put a full bottle of techron in the tank and only filled up 6 gallons, driving down the freeway and the car starts bucking and died on me... figured out I clogged the 3rd cat, opened up the cut outs and it runs fine... I know it says to fill up a whole tank but i'm still staying away from using that stuff anymore...

unless someone tampered with the product it wasn't the cause of your cat failure, nor the bucking or dying.

you mixed it "extra strong" but unless you exceed 20% of your fuel volume, you aren't gonna hurt anything.

You already had an underlying condition otherwise you wouldn't have mixed up a extra strong dose of techron.

Maybe the previous manifold volume issue had some underlying effects that weren't blatently obvious.

What made you put a bottle of tecron on 6 gallons.

tell us "the whole story"..
HAHA
 
FWIW I turned off the rear 02's on my car just prior "within minutes" of getting an inspection
to see if a p1000 code or lack of rear o2's would fail my 98LSC

it passed, so I went back to the office and turned my rear 02's back and and went on with my life.
lol
 
Sounds more like a afr problem to me...

I just don't think there is anything that comes in a bottle that small that could bone a cat...
 
+1 definetely a unburnt fuel entering the exhaust issue, That is the number one reason cats fail, poor maintenance. But also how many miles does the car have, cause if you ask me a cat that far back wouldnt reach an optimum temp to burn efficently and the first two would already have flashed and burnt most of the unspent fuel. So in turn maybe the underlying problem could have been this cat, until it finally plugged. :rolleyes:
 
No, just because it doesnt have 02 sensors after it does not mean it is not a cat. On the passenger side of the car the first cat is part of the pipe on the driver side it is part of the manifold. Any post OBD2 car [96 and newer] has a catalyst efficency o2 sensor after the first set of cats. Now fomoco does call this a resonator, but it has all the precious metals a cat does and if you go to replace this part you will Know in the wallet that it is a cat for sure. I sell alot of the cats that I remove to an old deaf guy that extracts the metals himself. He pays for these like anyother cat made. THIS IS A CAT! :D

Meh. I am still removing mine in a month or so with Genos exhaust. :D

I was searching last night trying to find what exactly it is and I found this place that sells the drivers manifold with the cat attached for $280 brand spankin new and they sell the passenger side cat with the third cat/resonator for $304 brand new. Supposed to be NOS components and a direct bolt in. Sounded like good prices to me.
 
I think it was because I had the fuel pressure jacked up for about 2 weeks, it was at around 49psi and running rich, also the Magnaflow cat I got was the old style one which is poor quality, that combined with the strong techron mix killed it. X pipe is going in it's place... I checked the plugs and the car is (was?) running a bit rich. I backed down the fuel pressure...
 

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