WenmarOpen by Wenmar Pro

Service bulletins for the 2021 Audi A4

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

1057 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
A9120392061490_12020-12-04. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION. This bulletin covers Audi connect: oil level in the myAudi app is implausible
A1720112060750_12020-11-05. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION; EQUIPMENT. This bulletin contains instructions for using the UV additive to find engine oil leaks.
A1520352053278_42020-11-05. Service bulletin. ENGINE; STRUCTURE:BODY. This bulletin contains repair instructions for 3.0 and 2.9 TFSI engines that have oil loss around the engine compartment, front end, and underbody.
A0020422045316_52020-11-05. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ENGINE AND ENGINE COOLING:ENGINE. This bulletin contains information for diagnosing the Start/Stop system.
A9020682059891_22020-10-06. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This informational bulletin directs you to read the SSP and not perform any repairs for the concern.
A9020652032113_42020-09-03. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:COOLING SYSTEM. This information bulletin contains a background on the outside air temperature reading.
A0120832060429_12020-09-03. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This bulletin contains instructions for when there may be a noise from the exhaust flap or there are DTCs sporadically stored in the ECM.
2010-2021EngOil2020-09-03. Service bulletin. ENGINE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. New document
A1920042025303_12020-07-07. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin contains instructions for identifying and mixing factory fill coolants.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.