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Catylitic converter in my Audi A4

Over the summer my check engine light came on in my 2001 Audi A4 even though the car was driving fine. The dealer told me the catylitic converter would need to be replaced…eventually, before it got inspected. Just this week the check engine light started blinking and the car shakes when I drive it. It feels like not quite enough gas is getting to the engine. Fortunately, it shifts fine. Is it safe to drive and how much is this going to cost me???

So, you’ve been driving whit the check engine light on since summer, is that correct? Why would you do that?

The light is an early warning system. You ignore the light at your peril, because whatever is wrong only gets worse if you ignore it.

Now the light is blinking, which means things are much worse, and the car is no longer “driving fine.”

There is no way to know what’s wrong with the car until someone scans the computer for trouble codes. It could be a development on the original problem, or there could be several problems, which you would not have been warned about because the light was already on.

It’s an Audi. It’s going to cost money. How much depends on how many problems the car has.

What does the owner’s manual say about a blinking light? If it says not to drive the car, then I’d have it trucked to the dealer or a mechanic. I would NOT try to use this car as daily transportation until it has been repaired. It may quit running altogether.

Do you know what the trouble codes are? If you post them here, we can help you determine what the causes might be. You can then use this information to understand what your mechanic suggests doing. If you don’t have the codes now, you can go to a car parts store and get the codes read. Many of them have code readers and will help you use them - for free.

One more thing: catalytic converters are guaranteed for 8 years, I believe. If you need a new one, it’s a warranty job; free to you. Get it done, if you need it, before the warranty expires. Your car is at least 7 years old - tick-tock, tick-tock…

Driving with the light on, will hide any new problems that come up. Now you have a new problem, or a worsening one.

Blinking generally means DON’T DRIVE THE CAR! Damage may result.

I have a code reader, but if I did not I would recommend trying to borrow one or have the car towed to one. Driving it could cost you,

Hopefully you are within the 8yr(yes)/80,000(maybe) mile period. If it is the Audi pays for the cat converter.

Blinking CEL means fix really soon don’t ignore.

Sounds to me like maintenance is being neglected; spark plugs, wires, fuel filter, etc. Maybe neglect is the indirect cause of the converter malfunction.

How many miles on the car?
Did the dealer recommend a repair 6 months ago and did you refuse the repair?
When was the last time, if ever, the plugs, etc. were changed?

You should keep in mind the little things often become big things if left unattended.

I too have a 2001 A4 2.8L with 91,000 miles and need 2 catalytic converters to pass inspection. My mechanic told me it would be around $2,800. He recommended against after market converters, but they are half to a third the price of the Audi part. Any thoughts on this? I am in a quandary as to whether it is worth it at this point. I do love driving the car…

I would be inclined to install aftermarket. Realize some aftermarket are the OEM parts. Audi does not make cat converters, another company does and Audi badges them.