OVERVIEW
Original hardware for accessory belt tensioner mounting
The N-019-543-3 Genuine VW/Audi accessory belt tensioner bolt is an M8x50 fastener used to secure the tensioner at the original engine mounting position. The tensioner controls belt tension, while its mounting hardware holds the assembly against its support. Correctly specified hardware matters when replacing the tensioner or correcting damaged fasteners found during an accessory-drive repair.
Technical details
- Original part number: N-019-543-3 / N0195433.
- Specification: M8 nominal thread diameter and 50 mm bolt length.
- Head design: external hex with an integral collar beneath the head.
- Supersedes: N-019-543-2 at the corresponding original catalog positions.
- Included: one bolt. Tensioner, pulley, belt and other mounting hardware are sold separately.
The collar provides the specified bearing surface at the mounting joint. Bolt length and the original attachment specification must match: a shorter or longer generic M8 fastener can alter thread engagement or bottom out before the joint is properly clamped. Verify the engine and exact bolt position rather than selecting hardware by diameter alone.
Common reasons to replace
- Damaged hex head: rounded flats or prior tool damage can prevent dependable tightening and later service.
- Thread damage: cross-threading, corrosion or damage during removal can compromise the mounting connection.
- Missing or incorrect hardware: previous tensioner work may leave a substitute bolt with the wrong length or bearing arrangement.
- Replacement required during tensioner service: follow the specific factory procedure regarding reuse and any pre-applied locking treatment.
A squealing belt, pulley noise or unstable belt tracking does not establish that this bolt is the cause. Inspect the belt, tensioner, pulleys, component alignment and mounting surface together. Replace the defective component and repair any damaged threaded mounting hole before installing new hardware.
Fitment data sheet
| Vehicle | Model years | Engine | Configuration | Application restrictions |
|---|---|---|---|---|
| Audi A4 | 1997–2001 | 1.8L turbo four-cylinder gasoline | B5 Sedan / Avant; front-wheel drive or quattro; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Audi A4 | 2002–2005 | 1.8L turbo four-cylinder gasoline | B6 Sedan / Avant; 2005 B6 body only; front-wheel drive or quattro; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Audi A4 | 2003–2006 | 1.8L turbo four-cylinder gasoline | B6 Cabriolet; front-wheel drive or quattro; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Audi A4 | 2005–2008 | 2.0L turbo four-cylinder gasoline | B7 Sedan / Avant; 2005 new B7 body only; front-wheel drive or quattro; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Audi A4 | 2007–2009 | 2.0L turbo four-cylinder gasoline | B7 Cabriolet; front-wheel drive or quattro; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Audi TT | 2000–2005 | 1.8L turbo four-cylinder gasoline, 180 hp | Mk1 Coupe / Roadster; front-wheel drive or quattro; Roadster from 2001; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Volkswagen GTI | 2000–2005 | 1.8L turbo four-cylinder gasoline | Mk4 Hatchback; includes 2002 337 and 2003 20th Anniversary; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Volkswagen Jetta | 2000–2005 | 1.8L turbo four-cylinder gasoline | Mk4 Sedan; 2005 old body only; GLI 1.8T from 2004.5; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Volkswagen Jetta Wagon | 2002–2005 | 1.8L turbo four-cylinder gasoline | Mk4 Wagon; No separate transmission restriction for the confirmed engine attachment | Accessory belt tensioner-to-engine fastening only where the original parts diagram specifies N-019-543-3. Match the exact mounting point; not a replacement for every tensioner bolt. |
| Audi TT | 2001–2006 | 1.8L turbo four-cylinder gasoline, 225 hp | 8N Coupe or Roadster; quattro; Six-speed manual; quattro | Original accessory belt tensioner mounting bolt N-019-543-3; match exact tensioner and engine attachment. Excludes 3.2L VR6. |
Service and ordering guidance
Confirm the part number for the vehicle identification number, engine and tensioner mounting position. There may be multiple fasteners on one tensioner assembly. This listing is for one M8x50 bolt and does not include a complete mounting set. Release the belt load and support the assembly as directed by the repair procedure before loosening its mount.
Use the prescribed tightening value, sequence and thread preparation for that exact engine. Do not infer torque from bolt diameter or the appearance of the archive photograph. The image shows a colored patch on the thread; the photograph alone does not identify its chemistry or authorize additional thread-locking compound. Follow the manufacturer’s instructions for the supplied fastener. Recheck the belt routing and tensioner position before operating the engine.