Colin Joseph – 06/15/2026
Yes. Audi requires premium unleaded gasoline across its lineup, rated at 91 octane or higher. This applies to the A4, A6, Q5, Q7, and virtually every other current Audi model. It is not a suggestion or a preference. The engines are designed and tuned for premium fuel, and the vehicle's performance, fuel economy, and long-term engine health are all calibrated around it.
The distinction between "required" and "recommended" matters here. Some manufacturers say premium is recommended but the car will run on regular. Audi says required, and means it. The turbocharged engines in Audi's lineup are built to specific compression ratios and ignition timing that depend on the higher octane rating of premium fuel to function correctly.
If you bought a used 2021 A4 from a private seller and have been putting regular in it, stop. Switch to premium at your next fill-up. A tank or two of regular will not destroy the engine, but making a habit of it will cause problems over time.
Modern Audi engines have knock sensors that detect low-octane fuel and automatically slow the ignition timing to compensate. This protects the engine from immediate damage in a low-octane situation, but it does so by reducing performance and fuel efficiency. You will get less power and worse mileage when running regular in an Audi tuned for premium.
Used consistently over time, regular fuel in a premium-required engine puts the knock sensors under sustained stress, increases carbon buildup on intake valves, and can lead to premature wear. The short-term savings at the pump are not worth the long-term cost to the engine.
If you are filling up on Long Island and want to be sure you are using the right fuel, look for 91 or 93 octane at the pump. Most stations in Nassau County carry both. Either is fine for your A4.
This is one of the questions that confuses new Audi owners most, because the answer is different from what they are used to hearing. Audi does not follow a fixed 3,000 or 5,000 mile oil change schedule. Instead, the vehicle monitors engine conditions and tells you when it actually needs an oil change through the Audi oil quality monitoring system.
For most Audi drivers doing typical mixed driving, oil change intervals land somewhere between 10,000 and 15,000 miles. That range is wider than most people expect. How often you actually need a change depends on your driving habits, the climate you are driving in, and how hard the engine is working. Short trips in cold weather burn through oil quality faster than steady highway driving.
The important thing is to follow the vehicle's indicator, not the sticker the last shop put on your windshield. Audi's monitoring system is real and it works. When the service indicator appears in the driver information display, schedule the oil service. Do not ignore it, but also do not rush to a shop after 3,000 miles because that is what you did with your last car.
On a used 2021 A4 bought from a private seller, the first thing worth doing is confirming when the last oil service was performed and what oil was used. Audi requires a specific oil specification, typically 5W-30 or 5W-40 meeting Audi's VW 502 00 or 504 00 standard. Using the wrong oil grade shortens the service life and can affect the monitoring system's accuracy. A quick oil service at Audi Great Neck will put you on the right oil and reset the service interval correctly.
The oil quality monitoring system, part of Audi's broader service interval display, continuously evaluates the condition of the engine oil based on driving patterns, temperature, engine load, and time. It does not use a physical sensor in the oil pan. It uses algorithms that model oil degradation based on how the vehicle is actually being driven.
When the system determines the oil is nearing the end of its useful life, it shows a service reminder in the instrument cluster. The display will show an oil can symbol along with the estimated mileage or time remaining before service is needed.
One thing new owners miss: the system also monitors other service items beyond oil, including brake fluid, air filter, and spark plugs. When any of these approach their service threshold, the cluster will show a corresponding reminder. None of these should be dismissed. They are calculated based on actual vehicle use, not arbitrary calendar intervals.
For a 2021 A4, the service history from the previous owner tells you a lot. Ask for it if you have not already. If you cannot get it, a multi-point inspection at Audi Great Neck will establish a baseline for where the car stands.
The key service items to understand for a vehicle in the 30,000 to 60,000 mile range:
Audi Care is a prepaid scheduled maintenance plan covering the first four factory-specified service visits at 10,000, 20,000, 30,000, and 40,000 miles. It includes oil and filter changes, brake fluid, cabin filter, engine air filter, and multi-point inspections at each interval.
For a new Audi purchase, Audi Care is worth serious consideration. The plan locks in current service pricing and can be rolled into the financing, spreading the cost over the loan term. Individually, those four service visits cost more than the plan price when paid out of pocket at current dealer labour rates.
For a used A4 bought privately, the standard Audi Care plan is no longer available since it must be purchased through an authorized dealer. However, if your A4 still has factory warranty coverage remaining, ask the Audi Great Neck service team about Audi Care Select packages that cover higher-mileage intervals. These are available separately and cover the 50,000, 60,000, and 70,000 mile services.
The MMI, which stands for Multi Media Interface, is Audi's infotainment and vehicle control system. On the 2021 A4, it uses a touchscreen interface rather than the older rotary controller found on earlier Audis. The basic layout puts navigation, media, phone, and vehicle settings on the main screen with quick-access shortcuts along the bottom edge.
A few things worth knowing early:
The home button in the lower left of the screen returns you to the main menu from anywhere in the system. If you get lost navigating sub-menus, it is the fastest way back to a familiar screen.
Swipe gestures work on the MMI screen the same way they do on a smartphone. Swipe left or right to move between main categories. Tap and hold on certain tiles to rearrange the home screen layout.
Apple CarPlay and Android Auto are both available on the 2021 A4 and connect wirelessly on most configurations. If yours requires a cable, check the USB-A port on the center console. Wireless CarPlay can be enabled in Settings under Connectivity if it is not already on.
The Virtual Cockpit is the 12.3-inch digital instrument cluster behind the steering wheel. It has two display modes toggled by a button on the left spoke of the steering wheel. In Classic mode, the traditional speedometer and tachometer take up most of the display with a smaller map or media view in the center. In Sport mode, the navigation map or media information expands to fill most of the screen with smaller instrument readouts on the sides. Most drivers settle on Classic for daily use and switch to Sport when navigating unfamiliar areas.
The driver information display in the center of the Virtual Cockpit is where your service reminders, range, fuel economy data, and trip computer information live. Scroll through it using the left steering wheel controls. This is also where Audi's oil quality monitoring alerts appear.
Every new and used Audi purchased at Audi Great Neck currently includes the Great Neck Gratitude Package at no additional charge. It is a complimentary protection bundle included for a limited time, and it covers three things that matter most in the first year of ownership.
Wheel Protection. One year of cosmetic rim protection. Long Island roads, particularly on the Northern State and the LIE, take a toll on wheels. This covers cosmetic rim damage and keeps your Audi looking the way it should.
Key Replacement. One-year contract coverage for the loss or damage of your Audi key. A replacement Audi key fob is an expensive proposition without coverage. This takes that risk off the table for the first year.
Exterior Paint Protection. A one-year chemical application that protects your Audi's exterior finish from everyday environmental elements, road salt, bird droppings, tree sap, and general weathering.
If you bought your Audi from a private seller, these benefits are not available retroactively. But if you are considering a new or used Audi through Audi Great Neck, the Gratitude Package is included at no charge and adds meaningful protection from day one.
Audi Great Neck is an authorized Audi dealer with factory-trained technicians and genuine Audi parts. Service visits for routine maintenance, warranty work, and recall repairs are all handled in-house. If you bought your A4 privately and have never had it serviced at an authorized dealer, scheduling a first visit is worthwhile for a few reasons.
The service team can pull the vehicle's service history from Audi's system, which may show records even if the previous owner did not hand over paperwork. They can also confirm the current status of any open recalls on the VIN, check the oil specification that was last used, and establish a service baseline going forward.
Scheduling a service appointment online takes a few minutes. If you have specific concerns about the A4 you bought, note them in the appointment comments so the advisor can allocate time accordingly.