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Catalytic Converter clogged on 2001 Mazda 626?

About a month and a half ago, just before I was to take an 8 hour trip, the check engine light on my 2001 Mazda 626, 120k, came on. To be safe, I took it to my mechanic, who scanned the computer and told me that the catalytic converter was either bad or clogged (he couldn’t tell which without taking the part off which would cost me app. $300) and that it needed to be replaced.

He recommended me to not drive long distances and to have it replaced soon. Since it will cost around $1500 and I haven’t had the money, I haven’t had it fixed yet but have been driving it, only around town though.

My question is the following (and as I know nothing about cars, please excuse my ignorance)… Is there any way to know if the cat is actually clogged. (Btw, I’ve noticed no change in the car’s performance, no loss of power or change in gas mileage.) Is it dangerous to continue to drive the car? If there was a serious problem with the cat, would the check engine light not come back on? (It went off after a few days the first time it came on and hasn’t come back on since.)

I need to drive about 1300 miles home for Christmas and could have the cat replaced there for MUCH cheaper by a mechanic who’s a family friend if it is necessary. But I’m not sure if it’s wise to make such a long trip. At the same time, now that I’ve been driving it for awhile with seemingly no problems or symptoms, I’m wondering if something really is wrong…?

A little background on the car… I bought it in 2005 with 60,000k from someone that had owned it for a few years. It was in good condition and had been well-maintained. Since I’ve owned it, the car has had regular maintenance - regular oil changes, fluid levels checked frequently, fuel and air filters changed, timing belts replaced, new spark plugs, new brakes, and last year, the transmission (unfortunately) had to be completely replaced.

Any advice or comments would be greatly appreciated. THanks in advance!

You can find aftermarket catalytic converters for much cheaper than an actual direct factory replacement

If the CEL turned itself off you have nothing to worry about, at least until it comes back on.

I suggest you get another opinion regarding the catalytic converter. Not knowing the exact codes from the computer makes it difficult to make an educated guess, but it’s entirely possible that the problem is (or was) something much less expensive than a new cat.

The CEL only comes on when the computer detects something operating outside normal parameters. If the light went off it means everything is now normal. Even if the light comes back on, it does not mean imminent disaster. The light is an early warning system, and it means you should have things checked at your earliest convenience.

There may be nothing wrong with the cat. Maybe an O2 sensor is reaching the end of its life, but there’s nothing here to indicate a bad cat except the mechanics opinion, and we don’t know what the code(s) indicated.

I suggest you check the fluid levels, make sure the tires are properly inflated (including the spare), and enjoy your holiday trip home. Don’t worry about the light unless it comes on, and if it does, have it checked when you reach your destination.

I have a 2002 Mazda MPV. The CEL came on in Nov 2008. I took it in for diagnostics without delay and was told it was a non-specific transmission code. I have made sure the gas cap is always on well. Over the last couple months the CEL has gone off for periods of a few days, but it always seems to come back on. The first place I took it said the non-specific problem would not cause me to have a wreck or drop the transmission and to drive it that way. I talked to someone at the Mazda dealer and he also said not to worry (but he was selling me a motorcycle). Now the Mazda dealer in our area has declared Chapter 7 bankruptcy, wiping out the 7 surrounding dealerships I had available. I could look up the code again–it’s in my car. So, does the on and off nature (mostly on) of the CEL mean something?