Model Reports
8 min readUpdated 11 Sep 2026
DVSA open data · 1,048 tests analysed
Seat Leon 2004: reliability & common MOT faults
408 first-attempt MOT failures were recorded on the 2004 Seat Leon in 2025. The item recorded most often on them was Rbt (sp). Figures are among first-attempt failed MOT tests, not among all tests.
Petrol Leons passed first time 2.6 pp more often than diesel ones (61.8% of 692 vs 59.2% of 353).
First-attempt pass
61.1%
of 1,048 first tests (2025)
First tests
1,048
test year 2025
Failed first attempts
408
failed first-attempt tests
Most common fail
13.0%
Rbt (sp)
MOT pass rates
First-attempt and official-style rates among class 4 first tests of the year.
First-attempt pass
61.1%
of 1,048 first tests (2025)
Official-style pass
69.4%
incl. same-day PRS fixes
First tests
1,048
class 4 · first MOT of the year
Typical age 21.0 yrs · median mileage 133,778 mi
vs 2024:
+0.1 pp first-attempt
Note:
Class 4 cars · first MOT of the year per vehicle · P/PRS/F outcomes (2025 data).
PRS (fixed at the station the same day) counts as a fail in the first-attempt rate.
Raw outcomes for this cohort — not adjusted for age, mileage, or peer mix.
MOT doesn't test engine or gearbox internals.
Advisories
Notes recorded at the test that appear more often than on similar cars.
Advisory notes recorded on failed first-attempt tests that appear more often than on similar cars.
Advisory pattern
Location
Notes
vs similar cars
Share
Confidence
Exhaust system
Body, chassis, structure > Exhaust system
Any
44
×2.2
10.8%
Elevated
Service brake performance (rear)
Brakes > Brake performance > Service brake performance > Rbt > Service brake performance
Note: Advisories are not a fail rate — they flag issues noted at the test, often before they become failures.
If you are buying one
What this year's MOT record means for the decision in front of you.
On this year, prefer the petrol. The diesel cars passed first time 2.6 pp less often, on 353 tests.
Other Leon years worth knowing about
Newer cars always pass more often, so a plain "best year" list would just
rank by age. These are the years that beat or miss the trend their own
neighbouring years set — the only age-adjusted signal this data supports.
The items that failed 2004 Leons most
often, as a share of the year's failed first attempts. This is what goes
wrong, not what is unusual — the table further up the page covers that.
Rbt (sp) — recorded on 13.0% of failed first attempts
Every figure here is a first-attempt MOT rate from DVSA open data for this
model line. MOTs do not test engine or gearbox internals, so this is a
pre-purchase checklist, not a full reliability score.
FAQs
Short answers about how to read this model-year guide.
Petrol Leons passed first time 2.6 pp more often than diesel ones (61.8% of 692 vs 59.2% of 353). In 2025, 61.1% of 1,048 first MOTs on the 2004 Seat Leon passed first time (PRS — items fixed at the station the same day — counted as a fail). The official-style rate including PRS is 69.4%. Among 408 failed first-attempt MOT tests (test year 2025), we highlight MOT failure patterns that show up more often than on cars…
Ranked by how often they were actually recorded, the items that failed 2004 Seat Leons most often at the first attempt were Rbt (sp) (13.0%) — each as a share of the year's failed first attempts. That is what goes wrong on the car. It is a different question from which patterns are unusual for the class, which the common-faults table answers.
Advisories flag issues noted at the test and are not a fail rate. We show advisory patterns that appear more often than on similar cars 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 MOT failure patterns for the 2004 Seat Leon (registration year) using UK DVSA open data for the selected test year. Patterns are compared with cars of a similar age and mileage. It is a buyer checklist from MOT defect statistics — not a full service history or manufacturer service-bulletin 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.
About this data
How this page is built and what it can (and can't) say.
These figures come from UK MOT open data for this model year. We surface common failure patterns against similar cars — not a full reliability score, and not a pass/fail verdict on any individual vehicle.
20242025
What we include
UK Class 4 cars only. Normal MOT tests (not retests); first test per vehicle per calendar year; results pass, PRS, or fail.
Same-day repairs
PRS means the car 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.
How we compare
We compare this model year with other Class 4 cars of similar age and mileage in the same test year. This model family is left out of the peer group so the car is not measured against itself.
What this does not cover
MOTs do not cover engine internals, gearboxes, or many electronics — this is not a full reliability score.
Common faults come from MOT defect stats, not manufacturer TSBs or recalls.
Age and mileage matching reduces — but does not remove — differences in how cars were used and maintained.
We never invent pass rates, star scores, or ranks when those data marts are missing.