News and Reviews

Why did a catalytic converter fail so quickly?

John Paul, aka "the Car Doctor,'' answers readers' car-related questions.

By John Paul @johnfpaul

Q. This past New Year's Eve I heard a noise and thought the muffler had broken. I went to a chain repair shop and they told me I needed a new muffler and catalytic converter. I had the catalytic converter replaced by the same shop three years ago, at a cost of $1,285. My question is how a catalytic converter can fail in such a short time when the original lasted 10 years. I had the car repaired and I paid another $1,285.00. Later I called their corporate office believing I was taken advantage of and they refunded about half the cost. What do you think happened here? Should I give them more business or look elsewhere?

A. If the exhaust system was not damaged by outside forces (you drove over something) I would expect it to last much longer. According to the EPA's website: manufacturers of new converters are also required to provide a warranty on the converter shell and end pipes for 5 years or 50,000 miles, whichever comes first, and for 25,000 miles on converter emission performance. Providing you have not exceeded the warranty the replacement of the catalytic convertor should have been covered under warranty.

Q. My wife loves her 2010 CR-V which recently tuned 100,000 miles. I searched the vehicle's owner's manual but cannot find any info about replacing the timing belt. My question, is this a concern or does she just keep driving?

A. Your wife's Honda CR-V like many more cars today have switched back to timing chains. The timing chain should last the life of the vehicle.

Q. I have a 2000 Chrysler Town and Country van and I've discovered the heater/defroster blower motor will only operate in the high position. I have had many problems with this van over the years and the van has less than 70,000 miles on it. I think at this point I'm not ready to buy any more Chrysler vehicles.

A. Over the years Chrysler vehicles have had their share of quality problems. Today the latest vehicles seem to be much more trouble free. Regarding your van heater fan, this is a likely a simple repair. The symptom is typical of a faulty fan resistor. The part is less than $15 and the repair shouldn't take more than 30-45 minutes.

Q. My 2008 Chevy Trailblazer has the Check Engine light come on and off sporadically. Car is running great. Dealer did a diagnostic and told me there's a "skip,'' then took apart the engine and told me there's a leaky valve and the entire cylinder head needs to be replaced for a cost of $4,700. If their diagnosis is correct, can't they just repair the bad valve?

A. The cost of the repair is as much about labor as parts. It can take up to 24 hours to remove the cylinder head and resurface/recondition the existing parts, if the front cover needs to be removed and about 10 hours if it doesn't. If the entire cylinder head needs replacing the part is $800 as compared to an individual valve that may cost $15-$20 each. Considering the high cost of estimate I would get a second opinion. Regardless this repair will be expensive and even if just a minimum of work is needed the repair could still be $2000 with parts and labor.

Readers point out a mistake: In a past column a reader was looking for a large all-wheel-drive sedan and I made a few suggestions, Ford Taurus, Hyundai Genesis and Chrysler 300 are all certainly good choices. I also recommended the Toyota Avalon which is not all-wheel-drive, but with four snow tires can perform very well in wintery weather.

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