I just got a 02 A6 3.0L Quattro with 125k miles on it. I called the Audi dealership and gave them the VIN # to look up the service history. The prior owner did all the recommended maintenance at the dealership including the timing belt at 109k. At 120k, the prior owner complained of knocking noise when accelerating. He had a fuel injection service performed and it seems fine now. He also complained of intermittent Check Engine lights going on and off. They reset the computer module and I see no issues now. The dealership said I may need to replace a cat converter soon.

1) Any advice on what maintenance I should do now? Is it likely I will have a cam lobes issue?

2) What brand and weight of oil should I use?

 

Oil ... http://microsites.audiusa.com/ngw/09..._1997-2012.pdf ... at 5k-10k mile interval.

Cat converter ... O2 Simulator, mini catalytic Converter cel fix
Amazon.com: CRC 05063 Guaranteed To Pass Emissions Test Formula - 12 Fl Oz.: Automotive

Change transmission oil/filter, differential oils at 60k-80k mile interval.

 

Sounds like cam lobes issue to me. I'd use 0w-40 to make sure the oil reaches top easily.

Cats are a common failure for the 3.0.

 

Thanks for the input everyone.

Is it OK to go with synthetic Mobil 1 0W-40 now at 125k miles? The prior owner had work done at the dealership, so I do not know if they used dino oil.

Is it OK to go with an aftermarket cat?

 

The advantage of oem cats through a dealer is you should be able to strong-arm him into guaranteeing the CEL goes away or fix it (at no further charge). I am still fighting occasional CELs after installing Billy Boat cats. In retrospect, I should have lived with the CEL and used my Innova 3130 ($130) to clear it. Unless you have emissions checks in your state, my advice is ignore it.

 

Castrol is the sponsor ... Audi dealers use Castrol Syntec, also synthetic oil, change in 10k mi interval.