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Common problems by part

Kia Niro exhaust, emissions and leaks problems

DVSA MOT tests 2022–2025 · 84,396 MOT tests · Updated

At 3 years, 0.1 in 100 MOT tests of the Kia Niro failed on exhaust, emissions and leaks, against 0.5 for all class 4 vehicles the same age (all test years; 84,396 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), 87 MOT tests with a fail
  • By age: seen at 7 ages from 3 to 9 years, 237,586 MOT tests
  • Most common fail: Malfunction indicator lamp: inoperative or indicates a malfunction, 0.1 per 100 MOT tests

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

What the MOT tests show

What we know

0.1 fails per 100 MOT tests at 3 years, against 0.5 for all class 4 vehicles tested at 3 (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.

Kia Niro exhaust, emissions and leaks fails by age

Kia Niro exhaust, emissions and leaks fails per 100 MOT tests by ageSolid line: the Kia Niro. Dashed line: all cars the same age. The table below lists every value.0123 years: 0.1 per 100 (all cars 0.5), 84,396 MOT tests34 years: 0.2 per 100 (all cars 0.7), 65,791 MOT tests45 years: 0.3 per 100 (all cars 1.0), 42,883 MOT tests56 years: 0.5 per 100 (all cars 1.3), 24,006 MOT tests67 years: 0.6 per 100 (all cars 1.7), 13,373 MOT tests78 years: 0.9 per 100 (all cars 2.1), 5,852 MOT tests89 years: 0.9 per 100 (all cars 2.4), 1,285 MOT tests9
Fails per 100 MOT tests by age, all first-use years pooled. Kia Niro All class 4 vehicles the same age
AgeMOT testsFails per 100All class 4 vehicles the same age
384,3960.10.5
465,7910.20.7
542,8830.31.0
624,0060.51.3
713,3730.61.7
85,8520.92.1
91,2850.92.4

All first-use years of the Kia Niro pooled at each age, against all class 4 vehicles at that age over all 2022–2025 test years.

What fails in the exhaust, emissions and leaks at 3 years

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
  • Repairs ahead
  • Viewing checklist

See a sample report

By engine and fuel

  • 1.6 hybrid: 0.2 per 100 at 3 years, about average for hybrid class 4 vehicles the same age (all test years; 47,547 MOT tests)
  • 0.0 electric: 0.0 per 100 at 3 years, about average for electric class 4 vehicles the same age (all test years; 36,654 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.

Check one Kia Niro, not the average

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

Other Kia Niro problems

Exhaust, emissions and leaks on rival models

Questions people ask

Does the Kia Niro have more exhaust, emissions and leaks problems than other cars?

0.1 in 100 MOT tests at 3 years, against 0.5 for all class 4 vehicles the same age: about average by our test (all test years; 84,396 MOT tests).

How common are Kia Niro exhaust, emissions and leaks problems?

0.1 in 100 MOT tests at 3 years failed on exhaust, emissions and leaks, against 0.5 for all class 4 vehicles the same age (all test years; 84,396 MOT tests).

What is the most common Kia Niro exhaust, emissions and leaks fail?

0.1 in 100 MOT tests at 3 years: Malfunction indicator lamp: inoperative or indicates a malfunction (77 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, 237,586 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