I have a 1999 Audi A6 quattro with over 269,000 miles on the odometer. Since last summer I've had a Check Engine Light on. I had the codes run last summer and P0411 was the only one. I was told it was the secondary air pump and it wouldn't hurt the vehicle to run it until it was replaced.

I finally bought an OEM Aircpump & OEM hoses to fix it. I stopped today to check the codes and was told I have 14! They are as follows:
Codes:
P0411

P0303
P1435

P1136

P1421

P1425, P1472

P0134, P0154, P1196

P1196 &7,8,9
P1522

P1519

P0140

P0160

I think the first one is the air pump. What can you tell me about the rest of them? Are any of them more serious than any of the others?

As always, thank you AudiWorld!

I checked the codes and they were either that air pump or O2 sensors. One was a misfire and two had something to do with the camshaft.

I went to o'Reillys auto parts and had the codes cleared. I started it up and drove home. No Check engine lights came on and gas mileage is a stellar 23.3 mpg (I was 21-22 mpg).

I'll just watch it and see what happens (hopefully nothing will).

I took your advice: Most of the codes were either Secondary air pump related or had to do with O2 sensors. One was a cylinder misfire and two had to do with the csmshatt.

I went to O'Reillys auto parts and had the codes cleared. Started the vehicle and drove it home. No lights came on and gas mileage was a fine 23.3 mpg.

I'll just monitor it and hopefully the lights won't come back on.