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SEAT Leon exhaust, emissions and leaks problems

DVSA MOT tests 2022–2025 · 74,889 MOT tests · Updated

At 6 years, 0.8 in 100 MOT tests of the SEAT Leon failed on exhaust, emissions and leaks, against 1.3 for all class 4 vehicles the same age (all test years; 74,889 MOT tests) [1].

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  • Against all class 4 vehicles the same age: about average for all class 4 vehicles the same age (all test years), 575 MOT tests with a fail
  • By age: seen at 20 ages from 3 to 22 years, 739,732 MOT tests
  • Most common fail: Malfunction indicator lamp: inoperative or indicates a malfunction, 0.3 per 100 MOT tests

Figures are for the model as a whole, not for one car.

What the MOT tests show

What we know

0.8 fails per 100 MOT tests at 6 years, against 1.3 for all class 4 vehicles tested at 6 (all test years). That is about average.

Why it matters

An exhaust, emissions and leaks fail stops the car passing until it is fixed; the most common one is rated major by DVSA.

What to check

Start the car from cold and look for smoke at the exhaust, listen for blowing joints, and look under the engine and gearbox for fresh oil or fluid drips.

SEAT Leon exhaust, emissions and leaks fails by age

SEAT Leon exhaust, emissions and leaks fails per 100 MOT tests by ageSolid line: the SEAT Leon. Dashed line: all cars the same age. The table below lists every value.05103 years: 0.6 per 100 (all cars 0.5), 49,082 MOT tests34 years: 0.5 per 100 (all cars 0.7), 66,486 MOT tests5 years: 0.6 per 100 (all cars 1.0), 72,889 MOT tests56 years: 0.8 per 100 (all cars 1.3), 74,889 MOT tests7 years: 1.1 per 100 (all cars 1.7), 72,860 MOT tests78 years: 1.6 per 100 (all cars 2.1), 70,670 MOT tests9 years: 2.2 per 100 (all cars 2.4), 64,013 MOT tests910 years: 2.7 per 100 (all cars 2.8), 56,823 MOT tests11 years: 3.4 per 100 (all cars 3.2), 46,491 MOT tests1112 years: 4.0 per 100 (all cars 3.7), 33,751 MOT tests13 years: 4.9 per 100 (all cars 4.3), 27,075 MOT tests1314 years: 6.5 per 100 (all cars 5.1), 23,214 MOT tests15 years: 7.5 per 100 (all cars 5.7), 21,664 MOT tests1516 years: 8.6 per 100 (all cars 6.2), 18,485 MOT tests17 years: 9.6 per 100 (all cars 6.5), 14,030 MOT tests1718 years: 9.0 per 100 (all cars 6.8), 10,142 MOT tests19 years: 10.0 per 100 (all cars 7.0), 7,134 MOT tests1920 years: 10.3 per 100 (all cars 7.0), 4,930 MOT tests21 years: 10.6 per 100 (all cars 7.1), 3,275 MOT tests2122 years: 9.5 per 100 (all cars 7.0), 1,829 MOT tests
Fails per 100 MOT tests by age, all first-use years pooled. SEAT Leon All class 4 vehicles the same age Shaded: over 18 years, survivors only.
AgeMOT testsFails per 100All class 4 vehicles the same age
349,0820.60.5
466,4860.50.7
572,8890.61.0
674,8890.81.3
772,8601.11.7
870,6701.62.1
964,0132.22.4
1056,8232.72.8
1146,4913.43.2
1233,7514.03.7
1327,0754.94.3
1423,2146.55.1
1521,6647.55.7
1618,4858.66.2
1714,0309.66.5
1810,1429.06.8
19*7,13410.07.0
20*4,93010.37.0
21*3,27510.67.1
22*1,8299.57.0

All first-use years of the SEAT Leon pooled at each age, against all class 4 vehicles at that age over all 2022–2025 test years. * Only survivors are still tested at this age.

What fails in the exhaust, emissions and leaks at 6 years

Fails

Advisories (not fails)

Diagnose engine warning light cost

Repair figures are estimates, not quotes: how we estimate repair costs.

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  • Model risks for this year and fuel
  • What similar cars did at their next MOT
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By engine and fuel

  • 2.0 diesel: 0.9 per 100 at 6 years, about average for diesel class 4 vehicles the same age (all test years; 10,466 MOT tests)
  • 1.6 diesel: 1.2 per 100 at 6 years, about average for diesel class 4 vehicles the same age (all test years; 9,759 MOT tests)
  • 1.4 petrol: 0.6 per 100 at 6 years, about average for petrol class 4 vehicles the same age (all test years; 20,415 MOT tests)
  • 1.5 petrol: 0.5 per 100 at 6 years, about average for petrol class 4 vehicles the same age (all test years; 12,695 MOT tests)
  • 1.2 petrol: 0.6 per 100 at 6 years, about average for petrol class 4 vehicles the same age (all test years; 8,565 MOT tests)
  • 2.0 petrol: 1.2 per 100 at 6 years, about average for petrol class 4 vehicles the same age (all test years; 8,499 MOT tests)

How to check on a test drive

Start the car from cold and look for smoke at the exhaust, listen for blowing joints, and look under the engine and gearbox for fresh oil or fluid drips.

The most common advisory here in MOT records: Engine oil leaks: leak, but not excessive.

Check one SEAT Leon, not the average

The figures here describe SEAT Leon cars as a group. These free tools answer for one car. Each line says what the tool reads.

Other SEAT Leon problems

Exhaust, emissions and leaks on rival models

Questions people ask

Does the SEAT Leon have more exhaust, emissions and leaks problems than other cars?

0.8 in 100 MOT tests at 6 years, against 1.3 for all class 4 vehicles the same age: about average by our test (all test years; 74,889 MOT tests).

How common are SEAT Leon exhaust, emissions and leaks problems?

0.8 in 100 MOT tests at 6 years failed on exhaust, emissions and leaks, against 1.3 for all class 4 vehicles the same age (all test years; 74,889 MOT tests).

What is the most common SEAT Leon exhaust, emissions and leaks fail?

0.3 in 100 MOT tests at 6 years: Malfunction indicator lamp: inoperative or indicates a malfunction (209 MOT tests with it).

Sources

  1. Driver and Vehicle Standards Agency, Anonymised MOT tests and results, 2022 to 2025. DVSA MOT data, Open Government Licence v3.0, 739,732 MOT tests. Accessed 7 Oct 2026.
  2. Office for National Statistics, Consumer price inflation, local price quotes (car repair items). ONS price quotes, series 610236. Accessed 7 Oct 2026.

Parts: against all class 4 vehicles at the same age, all 2022–2025 test years pooled, not adjusted for mileage. Breakdowns and non-MOT faults are not in this data. How we compare