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Old 12-09-2006, 04:49 PM   #1
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Default What causes Cat Converters to plug up?

Local Dealer has a 95 SE, says on the windshield that it "Needs Cat Converter" Please correct me if I am wrong, but isnt that USUALLY a symptom of something else not working right, ie burning coolant, cylinder not firing, poor maintence? Its a nice car otherwise, condition wise, I havent taken the time to visit with them or hear it run though. Its probably worth what they are asking for it in its current condition. MrsCrzy pointed out that it could have a whole host of other problems unseen and prefers to stick with our trusty LE'* and spend the $$$ on what we already have.
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Old 12-09-2006, 04:58 PM   #2
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severe improper a/f ratio. several dead sensors, causing a rich condition.



or a broken cat, I've had one before. it rattles when you hammer on it.
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Old 12-09-2006, 05:02 PM   #3
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Quote:
Originally Posted by Hans
severe improper a/f ratio. several dead sensors, causing a rich condition.



or a broken cat, I've had one before. it rattles when you hammer on it.
Forgot to mention that my father looked at it, they bought a beater at the same dealer for my sister to drive. Salesman told him that it had NO get up and go, so they figured the cat was plugged. They passed on it, she needed something to drive that didnt have to go straight to a shop. BTW, asking is 900 bucks. Maybe I can go look at it after a bit.

OTOH, 900 bucks in parts goes a LONG way towards fixing up the current LE'*
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Old 12-10-2006, 01:12 AM   #4
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Defective materials in manufacture can cause the inner material to break down and clog the cat. But if your dealership is doing things like just presuming the cat is plugged because a car has no get up and go, you should not buy a car from this dealer without getting the car thoroughly inspected by a qualified shop. In my entire lifetime I've experienced one plugged catalytic converter. I'd personally wager that plugged catalytic converters are one of the least common causes of a car "lacking get up and go", whereas more serious engine problems are probably *VASTLY* more common. Worn piston rings, worn valves, worn bearings, worn cam, being the most serious, and typical of things that a dealer might try to cover up by claiming ignorance and blaming on a plugged catalytic converter.

It begs the question, if the only thing wrong with the car is a plugged catalytic converter, why didn't the dealer just put a new catalytic converter on it?
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Old 12-10-2006, 01:44 AM   #5
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Quote:
Originally Posted by Bugsi
Defective materials in manufacture can cause the inner material to break down and clog the cat. But if your dealership is doing things like just presuming the cat is plugged because a car has no get up and go, you should not buy a car from this dealer without getting the car thoroughly inspected by a qualified shop. In my entire lifetime I've experienced one plugged catalytic converter. I'd personally wager that plugged catalytic converters are one of the least common causes of a car "lacking get up and go", whereas more serious engine problems are probably *VASTLY* more common. Worn piston rings, worn valves, worn bearings, worn cam, being the most serious, and typical of things that a dealer might try to cover up by claiming ignorance and blaming on a plugged catalytic converter.

It begs the question, if the only thing wrong with the car is a plugged catalytic converter, why didn't the dealer just put a new catalytic converter on it?
really good point. For a 200 dollar converter, they could get 2k for it. At least according to KBB.com Must be something else going on. I may check into it just to see, reckon they will let me pull plugs, maybe even run a comp test ?
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Old 12-10-2006, 10:40 AM   #6
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Default Re: What causes Cat Converters to plug up?

Quote:
Originally Posted by crzydmnd72
Local Dealer has a 95 SE, says on the windshield that it "Needs Cat Converter"
The Mrs. plan is actually a pretty good one...as Mrs clm2112 pokes me in the ribs.

Otherwise, I would take a look under the car and see if the cat is actually there or ask the dealer what the heck the message on the windscreen means. (It'* possible someone straight-piped the exhaust...though, I think it'* against the law for a dealer to knowingly sell one that has had the emissions gear tampered with.)
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Old 12-10-2006, 03:21 PM   #7
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Quote:
Originally Posted by crzydmnd72
Salesman told him that it had NO get up and go, so they figured the cat was plugged.
Sounds to me like the dealer has no clue what is wrong and is just guessing.
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Old 12-10-2006, 03:57 PM   #8
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The whole thing doesn't make much sense... wouldn't that dealer have to guarantee the beast under for a time under the lemon law?
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Old 12-10-2006, 08:41 PM   #9
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From what I've read, a plugged cat would limit power at high RPM
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Old 12-10-2006, 09:29 PM   #10
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Quote:
Originally Posted by Bugsi
Defective materials in manufacture can cause the inner material to break down and clog the cat. But if your dealership is doing things like just presuming the cat is plugged because a car has no get up and go, you should not buy a car from this dealer without getting the car thoroughly inspected by a qualified shop. In my entire lifetime I've experienced one plugged catalytic converter. I'd personally wager that plugged catalytic converters are one of the least common causes of a car "lacking get up and go", whereas more serious engine problems are probably *VASTLY* more common. Worn piston rings, worn valves, worn bearings, worn cam, being the most serious, and typical of things that a dealer might try to cover up by claiming ignorance and blaming on a plugged catalytic converter.

It begs the question, if the only thing wrong with the car is a plugged catalytic converter, why didn't the dealer just put a new catalytic converter on it?
You make it sounds like it is doomed to MAJOR engine work. Lack of get up and go could ALSO be dying fuel pump, bad FPR, bad wires, bad plugs, clogged injectors, very very dirty air filter, etc.
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