2021 Audi A4 Engine Parts

This table covers the seals at the Balance Shaft. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

This group shows a single part: MAHLE / CLEVITE 68079.

This table covers the bearings in the connecting-rod big ends. Typical signs include a growl that rises with speed, or play in the shaft or hub. Set preload the way the notes specify. A dry or crushed bearing fails quickly. Read more

2 Connecting Rod Bearing parts for the 2021 Audi A4 come from KING ENGINE BEARINGS.

Listed part numbers: KING ENGINE BEARINGS CR4637SV and KING ENGINE BEARINGS CR4637SX.

This table covers the Connecting Rod bolts. Read more

One part is listed for the 2021 Audi A4 — ELRING 038970.

This table covers lower / conversion gasket sets for oil-pan and related joints. Typical signs include the leaks that sent the engine or gearbox to the bench. Use every gasket the set is meant for that opening — leftover unused pieces usually belong to another configuration. Read more

5 Conversion / Lower Gasket Set parts for the 2021 Audi A4 come from 4 brands — AJUSA, ELRING, ENGINETECH and 1 other brand. The "Popular" part is ELRING 877300.

This group includes ELRING 877300, AJUSA 54262400 and AJUSA 54295400 and the remaining parts above.

This table covers the front and rear seals that keep oil in at the crankshaft. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

8 Crankshaft Seal parts are listed for the 2021 Audi A4, from ELRING, VICTOR REINZ, AJUSA and 3 other brands. ELRING 248300 carries the "Popular" badge.

Part numbers include ELRING 248300, ELRING 798660 and AJUSA 71007200, among others listed above.

This table covers the Crankshaft Seal covers. Read more

This group shows a single part: DORMAN 635696.

This table covers the bolts that clamp the cylinder head to the block. Read more

3 Cylinder Head Bolt parts for the 2021 Audi A4 come from 2 brands — AJUSA and VICTOR REINZ.

Part numbers include AJUSA 81054400, AJUSA 81077400 and VICTOR REINZ 141966401.

This table covers the head gaskets that seal the block to the cylinder head. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

7 Cylinder Head Gasket parts for the 2021 Audi A4 come from 4 brands — AJUSA, VICTOR REINZ, ELRING and 1 other brand. The "Popular" part is AJUSA 10202800.

Part numbers include AJUSA 10202800, ELRING 564670 and AJUSA 10269100, among others listed above.

This table covers multi-piece gasket sets for a cylinder-head job. Typical signs include the leaks that sent the engine or gearbox to the bench. Use every gasket the set is meant for that opening — leftover unused pieces usually belong to another configuration. Read more

5 Cylinder Head Gasket Set parts for the 2021 Audi A4 come from 2 brands — AJUSA and VICTOR REINZ.

Listed part numbers: AJUSA 52502400, AJUSA 52505500 and AJUSA 52626200, plus the other parts above.

This table covers the Engine covers. Read more

2 Engine Cover parts for the 2021 Audi A4 come from TECHPRO.

Listed part numbers: TECHPRO AU1228145 and TECHPRO AU1228141.

This table covers full gasket kits covering the joints opened in an engine rebuild. Typical signs include the leaks that sent the engine or gearbox to the bench. Use every gasket the set is meant for that opening — leftover unused pieces usually belong to another configuration. Read more

4 Engine Kit Gasket Set parts for the 2021 Audi A4 come from AJUSA.

Listed part numbers: AJUSA 50451400, AJUSA 50455100 and AJUSA 50558000, plus the other parts above.

This table covers the followers that drive a mechanical fuel pump off the camshaft. Read more

This group shows a single part: ASTEMO / HITACHI HCF3057.

This table covers the gaskets between the intake manifold and the cylinder head. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

7 Intake Manifold Gasket parts for the 2021 Audi A4 come from 5 brands — VICTOR REINZ, AJUSA, FEL-PRO and 2 other brands. The "Popular" part is FEL-PRO MS97518.

This group includes FEL-PRO MS97518, VICTOR REINZ 714278600 and AJUSA 13245500 and the remaining parts above.

This table covers the seals at the Intermediate Shaft. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

One part is listed for the 2021 Audi A4 — ELRING 299640.

This table covers the mounts that hold the engine to the chassis. Typical signs include a clunk on takeoff, a vibration at idle, or a separated rubber insert. Support the powertrain before unbolting a mount, and torque the fasteners in the notes. Read more

8 Motor Mount parts are listed for the 2021 Audi A4, from SKP, ANCHOR, DEA / MARMON RIDE CONTROL and 1 other brand. SKP SK10216 carries the "Popular" badge.

In the Economy grade, SKP supplies 2 parts: the catalog's value-priced group. A representative part number is SKP SK10216.

The Standard Replacement section lists 6 options from ANCHOR, DEA / MARMON RIDE CONTROL and WESTAR — built to original-equipment specification. ANCHOR 10215 is listed in this group.

Listed part numbers: SKP SK10216, SKP SK10215 and ANCHOR 10215, plus the other parts above.

This table covers the Motor Mount kits. Read more

One part is listed for the 2021 Audi A4 — ANCHOR 300966.

This table covers the engine oils listed by grade and specification for this engine. Typical signs include a low-oil lamp, knocking after a long interval, or oil that has gone thin and black well before the next service. Match the viscosity and spec in the notes (and on the filler cap). The tables group grades — they are not interchangeable. Read more

16 Oil parts are listed for the 2021 Audi A4, from PENTOSIN, LIQUI MOLY, VAICO and 2 other brands. LIQUI MOLY 20238 carries the "Popular" badge.

This table covers the heat exchangers that cool engine oil. Typical signs include oil at the cooler fittings, or coolant that looks like a milkshake. Pressure-test both circuits after a cooler swap — a leak here mixes oil and coolant. Read more

3 Oil Cooler parts are listed for the 2021 Audi A4, from DORMAN, HELLA and NISSENS.

This group includes DORMAN 918985, HELLA 366360581 and NISSENS 91607.

This table covers the gaskets that seal the Oil Cooler. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

3 Oil Cooler Gasket parts for the 2021 Audi A4 come from 3 brands — ELRING, FEL-PRO and MAHLE / CLEVITE.

Part numbers include ELRING 279610, FEL-PRO 73305 and MAHLE / CLEVITE B33478.

This table covers the drain plugs in the oil pan. Read more

4 Oil Drain Plug parts are listed for the 2021 Audi A4, from DORMAN, ELRING, REIN and 1 other brand.

This group includes DORMAN 090090, ELRING 588690 and REIN HWP0043 and the remaining parts above.

This table covers the Oil Drain Plug Removal tools. This is a service tool, not a wear part — match the application in the notes. Read more

One part is listed for the 2021 Audi A4 — DORMAN 090999.

This table covers the oil filters that screw onto this engine's filter mount. Typical signs include low oil pressure after a service, or a filter that will not spin off because the old gasket stayed on the block. Lube the new gasket and tighten to the spec on the box; a double-gasket install dumps the sump on the first drive. Read more

22 Oil Filter parts are listed for the 2021 Audi A4, from VAICO, WIX, FRAM and 13 other brands. WIX WL10396XP carries the "Popular" badge.

Economy: 8 parts, from VAICO, PRO-TEC, CHAMP / LUBER-FINER and 2 other brands. A representative part number is CHAMP / LUBER-FINER P1078.

In the High Performance / Heavy Duty grade, WIX and MOBIL supply 2 parts: grouped under the catalog's "High Performance / Heavy Duty" designation — the notes column spells out what sets them apart. A representative part number is WIX WL10396XP.

The Standard Replacement section: 8 options from HENGST, MANN, WIX and 5 other brands. HENGST E358H03D246 is listed in this group.

4 ungrouped parts are not assigned to a grade, with the same engine-level match.

This table covers the Oil Filter Adapter Gasket O-rings. Typical signs include a seep at a fitting or a housing that weeps after a service. Lube the new O-ring with the fluid it will see, and do not roll it into the groove. Read more

2 Oil Filter Adapter Gasket / O-Ring parts for the 2021 Audi A4 come from 2 brands — FEL-PRO and MAHLE / CLEVITE.

Listed part numbers: FEL-PRO 76367 and MAHLE / CLEVITE B33479.

This table covers the Oil Filter covers. Read more

3 Oil Filter Cover parts for the 2021 Audi A4 come from 3 brands — DORMAN, MOTORAD and ÜRO PARTS.

Part numbers include DORMAN 921169, MOTORAD MO319 and ÜRO PARTS 06L115401LPRM.

This table covers the seals at the Oil Filter Housing. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

One part is listed for the 2021 Audi A4 — ELRING 279630.

This table covers the Oil Level Sensor Gasket O-rings. Typical signs include a seep at a fitting or a housing that weeps after a service. Lube the new O-ring with the fluid it will see, and do not roll it into the groove. Read more

2 Oil Level Sensor Gasket / O-Ring parts are listed for the 2021 Audi A4, from AJUSA and ELRING.

This group includes AJUSA 01899000 and ELRING 351210.

This table covers the oil pans that hold the engine's oil sump. Read more

4 Oil Pan parts for the 2021 Audi A4 come from 4 brands — DORMAN, REIN, SPECTRA PREMIUM and 1 other brand.

Listed part numbers: DORMAN 264553, REIN ESK0240 and SPECTRA PREMIUM VWP60A, plus the other parts above.

This table covers the gaskets between the oil pan and the block. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

6 Oil Pan Gasket parts are listed for the 2021 Audi A4, from AJUSA, VICTOR REINZ and ELRING. AJUSA 16063100 carries the "Popular" badge.

Part numbers include AJUSA 16063100, VICTOR REINZ 703141410 and AJUSA 59016300, among others listed above.

This table covers the Oil pumps. Typical signs include noise from the pump, no pressure, or fluid that never arrives at the outlet. Prime or fill the pump as the notes require. A dry start is a common way to kill a new unit. Read more

One part is listed for the 2021 Audi A4 — VAICO V10000191.

This table covers the Oil Pump Chain tensioners. Typical signs include belt flutter, a chirp that returns after a new belt, or an arm that no longer damps. Replace the tensioner with the belt at higher mileage. Read more

One part is listed for the 2021 Audi A4 — INA ZT0273.

This table covers the Oil Pump Control Valve solenoids. Typical signs include a harsh or missing shift, or a code for this solenoid circuit. Check resistance and the connector before dropping the pan for a solenoid. Read more

2 Oil Pump Control Valve / Solenoid parts for the 2021 Audi A4 come from 2 brands — DORMAN and GATES.

Listed part numbers: DORMAN 916880 and GATES VVS263.

This table covers the Oil Temperature senders. Read more

This group shows a single part: VEMO V10720210.

This table covers the rocker arms that transfer cam motion to the valves. Read more

One part is listed for the 2021 Audi A4 — MELLING MR1349.

This table covers the Timing belts. Typical signs include squeal on cold start, cracked ribs, or glazing. Spin the tensioner and idlers by hand while the belt is off. Read more

This group shows a single part: DAYCO 95352.

This table covers the Timing Belt & component kits. Read more

One part is listed for the 2021 Audi A4 — GMB 34800923.

This table covers the Timing covers. Read more

This group shows a single part: DORMAN 635144.

This table covers the gaskets that seal the Timing Cover. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

4 Timing Cover Gasket parts are listed for the 2021 Audi A4, from ELRING and MAHLE / CLEVITE.

This group includes ELRING 893790, ELRING 893820 and ELRING 031320 and the remaining parts above.

This table covers the seals at the Timing Cover. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

One part is listed for the 2021 Audi A4 — SKF 17708.

This table covers the Torque Strut mounts. Typical signs include a clunk on takeoff, a vibration at idle, or a separated rubber insert. Support the powertrain before unbolting a mount, and torque the fasteners in the notes. Read more

2 Torque Strut Mount parts for the 2021 Audi A4 come from ANCHOR.

This group includes ANCHOR 10332 and ANCHOR 10333.

This table covers the turbochargers that compress intake air. Read more

One part is listed for the 2021 Audi A4 — VNE 7005081.

This table covers the Turbocharger Boost sensors. Typical signs include a warning lamp, a stored code, or a reading that drops out when the harness is wiggled. Inspect the connector and ground before replacing the sensor — wiring faults are often condemned as bad sensors. Read more

This group shows a single part: WELLS 5S13477.

This table covers the Turbocharger Diverter / Bypass valves. Typical signs include a circuit that will not hold, a whistle, or a code for this valve. A stuck valve is often debris. Clean the ports before installing the new one. Read more

4 Turbocharger Diverter / Bypass Valve parts are listed for the 2021 Audi A4, from DORMAN, PIERBURG, STANDARD MOTOR PRODUCTS and 1 other brand.

Listed part numbers: DORMAN 911240, PIERBURG 702901050 and STANDARD MOTOR PRODUCTS TBV1013, plus the other parts above.

This table covers the gaskets that seal the Turbocharger. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

2 Turbocharger Gasket parts for the 2021 Audi A4 come from AJUSA.

Part numbers include AJUSA JTC12304 and AJUSA JTC12738.

This table covers the fasteners that mount the turbocharger. Read more

This group shows a single part: ELRING 041450.

This table covers the Turbocharger Oil lines. Typical signs include a wet fitting, a rusted pipe, or a pressure loss in this circuit. Flare or thread the new line the way the notes specify; a kinked replacement will fail early. Read more

AJUSA supplies both parts for the 2021 Audi A4.

Part numbers include AJUSA OP10642 and AJUSA OP11334.

This table covers the Valve covers. Read more

This group shows a single part: VAICO V105778.

This table covers the gaskets that seal the valve cover to the cylinder head. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

2 Valve Cover Gasket parts are listed for the 2021 Audi A4, from ELRING and VICTOR REINZ.

This group includes ELRING 461682 and VICTOR REINZ 703141410.

This table covers the lifters / tappets that transfer cam motion to the valves. Read more

3 Valve Lifter parts are listed for the 2021 Audi A4, from AJUSA and MELLING.

This group includes AJUSA 85009000, AJUSA 85022200 and MELLING JB7532.

This table covers the keepers that lock each valve-spring retainer to the stem. Read more

This group shows a single part: MELLING VL1098.

This table covers the seals on each valve stem that control oil into the guides. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

7 Valve Stem Seal parts are listed for the 2021 Audi A4, from ELRING, MAHLE / CLEVITE, AJUSA and 1 other brand. ELRING 724590 carries the "Popular" badge.

This group includes ELRING 724590, MAHLE / CLEVITE SS45940A and AJUSA 12035500 and the remaining parts above.

This table covers the oil-control solenoids that command the cam phasers. Typical signs include a door or range that will not move, or a click with no motion. Confirm the command signal before replacing the actuator — a failed module looks the same. Read more

7 Variable Valve Timing (VVT) Solenoid / Actuator parts are listed for the 2021 Audi A4, from STANDARD MOTOR PRODUCTS, SPECTRA PREMIUM, HOLSTEIN and 3 other brands. SPECTRA PREMIUM VTS1199 carries the "Popular" badge.

Economy: 3 parts, from SPECTRA PREMIUM, HOLSTEIN and WELLS. A representative part number is SPECTRA PREMIUM VTS1199.

The Standard Replacement section: 4 options from STANDARD MOTOR PRODUCTS, PIERBURG and VAICO. PIERBURG 706117260 is listed in this group.

This group includes SPECTRA PREMIUM VTS1199, HOLSTEIN 2VTS0191 and WELLS 2T1228 and the remaining parts above.