Worst case scenario if a faulty catalyctic converter is left unreplaced?

doggie750

Per my mechanic, he claimed it will not damaged anything! Engine and fuel will stay the same as is. Should I fire him now
Need advice from you guys. Thanks!

Vehicle: MPV Mazda 2003 3.0L minivan

MikeC78

No, you'll be fine. However, your car will just result in more emissions to the environment and will probably fail SMOG.

strider

Unless it's coming apart internally. Then it could clog and cause some serious driveability problems. Not necessarily the most probable thing to happen, but it is possbile.

bobman1235

No, you'll be fine. Your car will just result in more emissions to the environment and will probably fail SMOG.

Uhh, is that true? If it's clogged you could certainly see some negative performance impacts, eventually coming to the point where exhaust would be backing up. Engines don't tend to like that.

dkg999

Until the converter plugs up, then the vehicle won't run. I had a friends car that one day just wouldn't start. The mechanic checked everything, worked on it most of one day, couldn't find anything amiss. Another friend of his worked at a dealership and had seen this scenario several times, dropped the exhaust pipe, and it fired right up. He said that when a cat converter stops working, it's only a matter of time until the insides come loose and cause a blockage.

MikeC78

bobman1235 wrote: »

Uhh, is that true? If it's clogged you could certainly see some negative performance impacts, eventually coming to the point where exhaust would be backing up. Engines don't tend to like that.

If it's clogged then there would be an issue. However, I'd be hard pressed to find an '03 in that bad of shape. I have a '94 van that has the original cat with no issues, but anything could be possible. If there isn't any driveability issues, I'd be hard pressed to assume it's clogged.

Anyway, what makes you think or your mechanic think that it's faulty? If it's throwing a code, I'd check the O2 sensor first, those usually go bad way before I'd claim a faulty cat. Sometimes you can get away with a good cleaning, usually they have to be replaced.

MikeC78

Anyway, you guys would be correct as to assume that'd be the worst case scenario.:) I'm trying to be a little optimistic here.

Seriously, I'd try to steer clear of replacing the CAT, they are not cheap to replace. I guess I'd wait until it caused more issues down the road and you are stuck somewhere.:o (worst case scenario)

Fongolio

I've had one clog up and get so hot it glowed red and started my carpet smoldering. Be careful.

SolidSqual

Fongolio wrote: »

I've had one clog up and get so hot it glowed red and started my carpet smoldering. Be careful.

+1 here. Led to an overheating issue in my tahoe.

billbillw

Yo Doggie, how many miles on that MPV? Most manufacturers have a pretty long warranty on emissions equipment, many times at least 80K and often they will extend for things like Cats. Check with Mazda USA or the local dealer.

strider

billbillw wrote: »

Yo Doggie, how many miles on that MPV? Most manufacturers have a pretty long warranty on emissions equipment, many times at least 80K and often they will extend for things like Cats. Check with Mazda USA or the local dealer.

Good call, completely slipped my mind.

heiney9

If it gets plugged bad enough it might get hot and could start glowing cherry red. If it gets to that point of being severely clogged you will damage your engine. Most newer cars use 2 or more oxygen sensors to lean/enrich the fuel mixture; among other sensors and devices. Extreme lean or rich conditions can do other damage if your not careful; worst case scenario.

Face

heiney9 wrote: »

If it gets plugged bad enough it might get hot and could start glowing cherry red. If it gets to that point of being severely clogged you will damage your engine. Most newer cars use 2 or more oxygen sensors to lean/enrich the fuel mixture; among other sensors and devices. Extreme lean or rich conditions can do other damage if your not careful; worst case scenario.

+1!

Damage, if not even cause a catastrophic failure.

Either replace it or have a "test pipe" installed until you can afford to replace it. Just be warned, a test pipe should trigger the SES light and will cause you to fail a emissions inspection. And if you get caught, it's a hefty fine.

bigaudiofanatic

I would replace it ASAP because you are hurting the environment more not to say that i care that much but i do in another way care.

heiney9

Also catalytic converters have come way down in price in the past 5-7 years. The dealer is ridiculously priced but aftermarket CC's are excellent and very inexpensive for most cars.

I would check your warranty as emissions parts have to function for a predetermined amount of time as mandated by the gov't and the manufacturer has to replace worn or faulty parts within some sort of warranty.

Face

8 years, 80,000 miles:
http://www.accessconnect.com/aftermarket-parts-warranty.htm

Kris Siegel

Well that's crazy timing. My cat appears to be going up as well on my 2001 Chevy Prizm. Damn thing has over 110k miles on it so I may just end up getting rid of it (it has other issues).

heiney9

I had a 1991 Volks GTI the cat went out at 130K, the insides rattled horribly and the exhaust smell would choke you. I replaced it with an OEM cat (not bought from the dealer) for $99 and I sold the car with 200K and it still worked like new.

Granted this was a few years ago. I let it go way too long and the resulting lean mixture burned up the cat.

H9

bigaudiofanatic

Our honda had its stock one on for the time we owned it 298k miles later it was gone but never had to replace the cat or anything rely big the only thing was a radiator.

sucks2beme

Here in Texas, they just check for codes on newer cars. No tailpipe check.
So as long as the cat doesn't set check engine, I'm good.
If it clogs, it's like the old potato in the tailpipe trick. It won't start.

John30_30

Don't wait until it clogs. When they disintegrate like that, they're "supposed" to just drop that set of baffles so the exhaust flows on. Sometimes yes, sometimes no.
If no, it'll screw with performance. Go to a muffler shop and either have them cut it out and replace with straight pipe, or replace it.
The real auto guys here can set this straight- that's just what I get from my buddy who owns a shop.

I'm pretty sure California mandates you have to have one, maybe states back East also because of the smog- I know out here in the Southwest, it's not law. Check your state regs to see if you can even legally put a pipe in.

Face

John30_30 wrote: »

I'm pretty sure California mandates you have to have one, maybe states back East also because of the smog- I know out here in the Southwest, it's not law. Check your state regs to see if you can even legally put a pipe in.

It's federal law that you must have one. Some states such as NY, CA, NJ, etc...have stricter standards than other states.

ben62670

I don't need one:)

Face

I should elaborate, if your car came from the factory with one, you need to have one on there.

Ben, we all know you're special.

BrettT1

They don't do any vehicle inspections in Oklahoma anymore. I see cars not road worthy quite often. I guess they don't care if someone gets hurt.

ben62670

Face wrote: »

I should elaborate, if your car came from the factory with one, you need to have one on there.

Ben, we all know you're special.

1968 Bronco:D
No seat belts either, but I am going to add them. Stopping real quick even with 35's, and 7.5 inches of lift being shorter than a CJ7 in wheelbase can be hairy even with 4w disc brakes:eek:

mantis

bigaudiofanatic wrote: »

I would replace it ASAP because you are hurting the environment more not to say that i care that much but i do in another way care.

+1. You gotta replace it anyway so why wait? I know spending the money on it sucks but it's something you have to do.

It will start to cost you money in gas, it will hurt performance after it starts to break down, then your car will not start once it closes completely.

Jstas

If you tamper with a emissions control system on your vehicle with less than 80,000 miles on it and it ain't broken, don't get caught because fines are stiff and if the judge feels pissy that day, a first offense brings up to 2 years in jail with it. And that's not sissy county or state jail either. That's Federal, pound-me-in-the-**** jail. Oh yeah, your hot rod you had when you went to jail, will have likely had it's appointment with the crusher long before you get out early on good behavior.

ND13

Most emission components are covered under warranty for 80k miles.

doggie750

thank you for all the input, much appreciated!!!!!!!