2002 Audi A4 quattro 3.0L (Oil and Filter) [Archive] - Audi Forums

: 2002 Audi A4 quattro 3.0L (Oil and Filter)

01-24-2012, 01:12 PM
Hey guys

I'm new to Audi-Forums, and actually this is my first Audi I've ever owned.

i purchased a 2002 Audi A4 quattro 3.0l and i absolutely love it, I've had the car for a week and the check engine light came on. I thew on my obd2 reader and apparently I have 6 misfires from each cylinder. I contacted the dealer i bought the car from they told me to bring it in. the day after i bought it, same thing, but the obd2 code reader gave me a error code of p0421 which was either a bad o2 sensor, or error from cold starts...it was really cold out that day here in Canada -40....but the temperature is much warmer this week...and one more thing....there's a really loud noise coming from the belt on the engine by the rad/ac condenser....when should these belts be changed and is this the timing belt?

what is the best recommended full synthetic oil and filter for audis? Mobil 1 perhaps? and what kind of filter should I use?

has any1 ever heard or know what can cause the misfire on all cylinders?

Thanks guys


01-25-2012, 05:08 AM
Congratulations on the new-to-you A4! My wife and I just love our pair of B6 A4 3.0L Quattro's! :)

The visible belt on the front of the engine near the AC-condenser/radiator is the serpentine belt; the timing-belt is well-buried under the front engine-cover (along with the thermostat and water-pump). Noise from the serpentine belt is pretty unusual unless something driven by the serpentine belt is failing/faulted, such as a "frozen/seized" AC-condenser (the interior climate-control system runs the AC year-round to manage the humidity levels in the car interior). The serpentine belt is usually changed as part of the timing-belt service (every 70K-miles/7-years, whichever comes first).

The multi-cylinder misfires could be the result of failed/failing ignition-coils. A long-term "Achilles's heel" for Audi/VW engines has been the issue of ignition-coils; Audi has sequenced through a lengthy series of revisions and the latest ignition-coil revision seems to have finally addressed the frequently-failing ignition coils. There is a recall; check with the dealership to see if your car is covered under the recall (which should result in 6 of the latest revision ignition coils being installed). :cool:

As to engine-oil; be certain to use an engine-oil that meets the VW/Audi 502.00 engine-oil specifications (it should be printed on the container label). Check the forum sponors, such as ECS Tuning (i.e., http://www.ecstuning.com/Audi-B6_A4-Quattro-V6_30v/Maintenance/Engine/Oil/); they're helpful folks who can provide you with guidance on your maintenance supply needs. BTW, Mobil 1 is no longer a pure synthetic engine-oil; it used to be a full synthetic, but Mobil got into a urination contest with competitors over the semantic definition of full-synthetic engine-oil, lost the battle and started using a blend of pure-sythetic engine-oil stocks and dino-oil stocks in order to match the cost structure of their competitors. ;)

For engine-oil filters, you're best bet is to use filters that match the capabilities of the OEM filter. In particular, ensure the physical size matches that of the OEM filter; many of the third-party engine-oil filters that claim to meet the OEM specifications are significantly smaller and present a much-smaller filter surface-area. The forum sponsors offer the OEM filter at very competitive prices as well as a range of other viable options (i.e., OEM / Performance Parts for Audi, BMW, Mercedes Benz, Mini, Porsche & Volkswagen - ECS Tuning (http://www.ecstuning.com/Audi-B6_A4-Quattro-V6_30v/Maintenance/Engine/Oil_Filter/)). :)

Good luck! :cool:

01-26-2012, 07:40 PM
Thanks so much for the reply

So after the multi mis-fire situation the other day, I went back out to my car and started the car up just to see if the battery light and check engine light is on for the hell of it, and sure enough they were!!! Now from past experience from other vehicles the only time a battery light comes on your dash this usually indicates that there's a problem with the alternator or electric system.

After about 2 mins of turning the car on, the car stalled on it's own. Tried starting back up with the key, but battery was dead.

I went inside to my house, grabbed my booster pack come out side to boost the car to put my meter on the alternator to see what the voltage out put would be....Before even attempting to do any of this i noticed the the serpentine belt loose and not wrapping around the alternator "Bingo" that would explain the battery light, stalling of the car, and most likely the misfires as there was not enough voltage going to all 6 cylinders on only battery life!!!

I got the car towed over to the dealership where the car was purchased from, they are replacing the serpentine belt, and from what I seen I think the tension-er pulley broke off the engine reason what the loud sound was from the start that I had mentioned in the post before this. I gave this dealer a heads up that I will be taking this car to the Audi dealership for a inspect after I'm done with them "which I SHOULD have done before I made the purchase", but as gullible as I am, My friend that works at this dealer ship did tell me it was a great car and was well taking care of, as it was a couple of older folks whom owned this car. so I took his word for it, and I'm not going to hate on him, because I know it's a great vehicle and one belt issue which eventually would of happened is not going to make me hate the car, but better safe then sorry. I might just get Audi to replace the Timing belt for the hell of it as well just so I wont have any headaches down the road. The Vehicle has about 79,000 km's which is about 49088 Miles which is great mileage for a 10 year old car in my opinion.