Model Reports 8 min read Updated 12 Jul 2026

Audi A4 2004: reliability & common MOT faults

Elevated MOT failure patterns for the 2004 Audi A4 include Linkage pins and bushes (front) (~8.3× peers) and Flexible brake hoses (rear) (~5.7× peers). Based on UK DVSA open data for test year 2025 (1,834 failed first-attempt tests), compared with similar age and mileage peers. Available test years: 2024, 2025.

1,834 failed first-attempt tests · 4,784 first tests (test year 2025)

Standout pattern: Linkage pins and bushes (front) — about 8.3× more often than on similar peer cars.

Key takeaways before you buy

  • Linkage pins and bushes (front): about 8.3× more often than similar cars
  • Flexible brake hoses (rear): about 5.7× more often than similar cars

Common faults

These are MOT failure patterns that show up more often on this registration year than on similar cars of the same class, age band, and mileage in the same test year (leave-one-out peer comparison; whole model family excluded).

Statistical patterns from MOT defect codes — not manufacturer TSBs, recalls, or a diagnosis of any individual car. Fail and advisory patterns are kept separate.

Based on 1,834 failed first-attempt tests in test year 2025.

Linkage pins and bushes (front)

This failure pattern appears about 8.3× more often than on similar peer cars — recorded on 125 failed first-attempt tests; 6.8% of failed tests for this model year.

Front · 125 failures · ×8.3 vs similar cars · 6.8% of failed first tests · Strong pattern — appears far more often than similar cars

Flexible brake hoses (rear)

This failure pattern appears about 5.7× more often than on similar peer cars — recorded on 115 failed first-attempt tests; 6.3% of failed tests for this model year.

Rear · 115 failures · ×5.7 vs similar cars · 6.3% of failed first tests · Strong pattern — appears far more often than similar cars

# Fault pattern Location Failures vs similar cars Share of fails Confidence
1 Linkage pins and bushes (front)
Suspension > Anti-roll bars > Linkage pins and bushes
 Front 125 ×8.3 6.8% Strong pattern — appears far more often than similar cars
2 Flexible brake hoses (rear)
Brakes > Flexible brake hoses
 Rear 115 ×5.7 6.3% Strong pattern — appears far more often than similar cars
3 Pins and bushes (front)
Suspension > Suspension arms > Pins and bushes
 Front 232 ×2.7 12.6% Possible elevated fault
4 Individual direction indicators (rear)
Lamps, reflectors and electrical equipment > Direction indicators > Flashing type > Individual direction indicators
 Rear 84 ×2.7 4.6% Possible elevated fault
5 Electronic stability control
Brakes > ABS / EBS / ESC > Electronic stability control
 Any 39 ×2.6 2.1% Possible elevated fault
6 Coil spring (rear)
Suspension > Springs > Coil springs > Coil spring
 Rear 117 ×2.4 6.4% Possible elevated fault
7 Anti-lock braking system
Brakes > ABS / EBS / ESC > Anti-lock braking system
 Any 154 ×2.3 8.4% Possible elevated fault
8 SRS malfunction indicator lamp
Seat belts and supplementary restraint systems > SRS malfunction indicator lamp
 Any 142 ×2.1 7.7% Possible elevated fault

Only patterns that clear minimum sample and elevation thresholds are shown (at least 20 failures and 2.0× peer lift).

Advisories

Advisory items recorded on failed first-attempt tests that appear elevated versus peers. Advisories are not a fail rate — they flag issues noted at the test, often before they become failures.

# Advisory pattern Location Notes vs similar cars Share Confidence
1 Linkage pins and bushes (front)
Suspension > Anti-roll bars > Linkage pins and bushes
 Front 149 ×6.8 8.1% Strong pattern — appears far more often than similar cars
2 Individual direction indicators (rear)
Lamps, reflectors and electrical equipment > Direction indicators > Flashing type > Individual direction indicators
 Rear 79 ×3.9 4.3% Possible elevated fault
3 Pins and bushes
Suspension > Suspension arms > Pins and bushes
 Any 26 ×3.7 1.4% Elevated vs peers
4 Flexible brake hoses (rear)
Brakes > Flexible brake hoses
 Rear 176 ×3.1 9.6% Strong pattern — appears far more often than similar cars
5 Pins and bushes (front)
Suspension > Suspension arms > Pins and bushes
 Front 450 ×3.0 24.5% Possible elevated fault
6 Sub-frame condition (rear)
Body, chassis, structure > Integral vehicle structure > Sub-frame > Sub-frame condition
 Rear 21 ×2.8 1.1% Elevated vs peers
7 Sub-frame (rear)
Suspension > Sub-frames > Sub-frame
 Rear 284 ×2.6 15.5% Elevated vs peers
8 Sub-frame mounting prescribed areas (rear)
Suspension > Sub-frames > Sub-frame mounting prescribed areas
 Rear 45 ×2.4 2.5% Elevated vs peers

FAQs

We do not show a single reliability score for the 2004 Audi A4 on this page. Among 1,834 failed first-attempt MOT tests (test year 2025), Linkage pins and bushes (front) appears more often than on similar peer cars (about 8.3× more often than peers; 125 observed failures; 6.8% of failed tests). Treat this as a pre-purchase checklist from DVSA open data — not a guarantee for any individual car.
Among failed first-attempt tests we surface patterns that appear more often than on similar peer cars. Top example: Linkage pins and bushes (front) (about 8.3× more often than peers; 125 observed failures; 6.8% of failed tests). These are statistical signals, not a diagnosis of any individual car.
Linkage pins and bushes (front) shows up more often than on similar peer cars (about 8.3× more often than peers; 125 observed failures; 6.8% of failed tests). That does not prove a causal design fault — age, mileage, and usage still matter. Treat it as a pre-purchase check point, not a manufacturer TSB.
Common MOT problem areas for the 2004 Audi A4 include Linkage pins and bushes (front), Flexible brake hoses (rear). These are elevated versus similar peer cars where lift clears our floors — not a full list of every possible fault on an individual car.
Advisories flag issues noted at the test and are not a fail rate. We show advisory patterns that look elevated versus peers among failed first-attempt tests, separate from common failure rows. Use them as early-warning checks, not as a pass/fail score.
This page highlights elevated MOT failure patterns for the 2004 Audi A4 (registration year) using UK DVSA open data for the selected test year. Patterns are ranked against similar age and mileage peers. It is a buyer checklist from MOT defect statistics — not a full service history or manufacturer TSB list.
No. MOT tests do not cover engine internals, gearboxes, or many electronic modules. Patterns here come from MOT defect statistics only and should not be read as engine or gearbox reliability scores.
PRS means the vehicle failed items that were fixed at the test station and then passed the same day. We count PRS as a first-attempt fail in headline rates so same-day repairs do not hide problems.

About this data

Universe. UK class 4 cars only; normal MOT tests (not retests); results pass, PRS, or fail; one first test per vehicle per calendar year.

PRS policy. PRS means the vehicle failed items that were fixed at the test station and then passed the same day. We count PRS as a first-attempt fail in headline rates so same-day repairs do not hide problems.

Peer baseline. We compare this model year with other class 4 cars of similar age and mileage in the same test year, excluding the whole model family so the car is not compared with itself (leave-one-out peer baseline).

Data years. Test years covered: 2024, 2025.

Limitations.

  • MOT tests do not cover engine internals, gearboxes, or many electronic modules — so this is not a full reliability score.
  • Common faults are inferred from MOT defect statistics, not manufacturer TSBs or recalls.
  • Matching on age and mileage reduces but does not remove every usage or maintenance difference between cars.
  • Pass rates and star scores appear only when those data marts are available; this page never invents them.

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Contains public sector information licensed under the Open Government Licence v3.0.

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