Buyer Research

2023 Audi A4 — Should You Buy One?

Typical asking price: $26,000–$36,000. There is 1 high-severity known issue you need to know before handing over a check.

Deciding between model years? Compare the 15 Audi A4 years we've written up →

Kestrel Take

Seven complaints and no recall on a car this new is a record too thin to rate anything: seven people filed, and most 2023 A4s are still inside Audi's four-year warranty, which keeps owners at the dealer rather than at NHTSA. What those seven say is worth hearing, though, because three of them are the same event — the car shutting itself off while moving, twice at highway speed — and a fourth is a burst of false safety warnings from the driver-assist sensors. The B9 A4 in its last year is an otherwise settled design: the 2.0 TFSI and seven-speed dual-clutch had been in this body since 2017. Buy one with the remaining factory warranty confirmed by VIN, a dealer service file, and a test drive long enough to include a highway merge; if the seller mentions 'a software thing' that made it stall, get the repair order, not the story.

What we checked

Checked against public records, 2026-09-25

NHTSA holds 7 owner complaints for the 2023 Audi A4, and no recall campaigns.

That is too small a record to read a pattern from, so we are not going to pretend otherwise — with numbers this low one owner moves the percentage by a lot. What has been filed is grouped under electrics and electronics (3), the engine (3), throttle and cruise control (1). Treat those as things to look at, not as the vehicle's known weaknesses. A thin file usually means few of these were sold or few owners filed. It is not evidence the vehicle is trouble-free, and the issues below are our own research rather than a reading of this record.

Counts come from the NHTSA complaint and recall database — free, public, and worth checking yourself.

Known Issues for the 2023 Audi A4

Ranked by wallet impact. These are documented, recurring problems — not freak accidents. How we decide that.

Car shuts itself off while driving — twice at highway speed in a seven-complaint recordHigh — wallet impact

Three of the seven filings describe the same thing from three different owners: the A4 shutting down electronically with no warning, once in the left lane on a highway at 45,000 miles, once in traffic on a nearly new car that jerked to a halt as if it had hit a wall, and once a car that 'died' after a run of false safety alerts. None of the three has a diagnosis on file, so we cannot tell you the part. On a 2023 the suspects are the 12-volt battery and its monitoring, the mild-hybrid belt starter-generator on the 45 TFSI, and control-unit software — all of which a dealer should have addressed under warranty, with a repair order to show for it. Ask the seller directly whether the car has ever stalled or shut off, and ask for every dealer visit. On the drive, do a cold start, then idle in traffic with the climate on, then merge onto a highway; any stumble, flicker of the dash or 'start-stop system fault' message is a reason to stop the purchase and read the service history.

Repair cost (estimate): $0–$400 for a battery or a software update under warranty; $1,200–$2,500 for a belt starter-generator or a control module out of warranty

Source: NHTSA complaints filed under electrics and electronics (3), the engine (3), throttle and cruise control (1).

Audi pre sense false alarms — every sensor lit at once, braking warnings with nothing aheadMedium

One owner had the pre sense system fire twice with no hazard in front of the car, then saw every safety-sensor warning light at the same moment while driving, and one filing each under forward collision avoidance and back-over prevention sit alongside. On this car the front radar behind the grille and the camera at the top of the windshield are the usual sources; a replaced windshield that was not recalibrated, a radar knocked out of alignment by a parking tap, or a dirty sensor will all do it. Check whether the windshield is original (look for the Audi logo etched in the glass) and ask whether any recalibration has been done. On the drive, switch pre sense to its default and watch for warnings on an empty road.

Repair cost (estimate): $150–$400 for a camera or radar recalibration; $800–$2,000 for a radar unit

Source: NHTSA complaints filed under the driver-assist and automatic braking systems (1), back over prevention (1).

2.0 TFSI coolant seeps and thermostat housing — check under the intake before the warranty endsMedium

The EA888 2.0 turbo in this A4 has a long service history behind it, and the fault that history keeps repeating is coolant: the plastic thermostat housing and water pump module at the front of the engine, and the coolant lines around the turbo, weep before they fail, and a low-coolant warning is often the first the owner hears of it. The 2023 record does not show it, and we are not claiming it does — it is what to look for on this engine at any age. Open the hood cold, look for pink or white crust on the housing below the intake and around the coolant reservoir, and check the reservoir level against the marks. Under Audi's four-year warranty this is a free repair; a month after it expires it is not.

Repair cost (estimate): $600–$1,500 for a water pump and thermostat module

Source: not yet checked against public records.

Doors lock themselves on every drive — a menu setting, not a faultLow

One owner filed because the A4 locks all four doors as soon as it moves, and the owner's manual itself warns that locked doors slow emergency workers. On this car the behaviour is a setting: the central locking menu in the MMI lets you turn automatic locking off, and the doors unlock from inside with one pull of the handle regardless. It is worth knowing so you do not pay a dealer to 'fix' it. While you are in the MMI, cycle through the vehicle settings and confirm the screen and controls respond without lag or a reboot.

Repair cost (estimate): $0–$100

Source: NHTSA complaints filed under electrics and electronics (3).

Walk-Away Red Flags

✗Any stall, stumble or dash flicker on the test drive, however brief
✗A 'start-stop system fault' or battery warning at start-up
✗Seller mentions the car 'once shut off' with no repair order to show
✗Pink or white crust around the thermostat housing or coolant reservoir
✗Safety-sensor warnings on an empty road with pre sense at its default setting

Good Signs

✓In-service date on the Audi warranty lookup leaving a year or more of factory coverage
✓Complete dealer service file with every software update listed
✓Original windshield with the Audi etching, or a replacement with a calibration invoice
✓A cold start, a traffic idle and a highway merge that all came off cleanly, with the dash steady throughout
✓Coolant reservoir at the full mark with a dry thermostat housing