Kia Optima 2019: reliability & common MOT faults

At a glance

How 1,531 first tests went in 2025.

Passed first time: 80 in every 100
Did not pass first time: 20 in every 100313 failed first-attempt tests
The typical car: 6 yearsabout 65,772 miles
First tests counted: 1,531

What failed most often

Tyre condition (rear)17 in every 100 failed tests

How we count this. Data: UK MOT open data, 2025. Only Class 4 cars on their first MOT of the year are counted. A car that fails and is fixed at the test station still counts as a fail in the first-attempt rate. These are raw results, not adjusted for age, mileage, or peer mix. The MOT does not test engine or gearbox internals.

Note:

These are patterns across 2019 Kia Optima vehicles in 2025, not a prediction that any one car will have them. Faults are grouped by part of the car. They come from MOT defect codes, not manufacturer bulletins, recalls or a diagnosis of any one car.

Noise, emissions and leaks

One fault: diesel engine warning light, 2.4 times as often as on similar cars.

Figures below are measured across the 313 failed first attempts in 2025 that had a mileage recorded, which allows a like-for-like comparison.

We only list faults with at least 20 failures and a rate of about 2.0 times that of similar cars, which keeps one-off results out of the list.

Diesel engine warning light

Failed on 32 first tests2.4 times as often as similar carsPossible evidence

What it means

An engine malfunction indicator lamp that is illuminated to show a malfunction is graded Major on a diesel, but only on the diesels the test covers, which depends on the vehicle type and when it was first used. DVSA lists it under exhaust emissions for compression ignition engines, and the detail line for the row also names an inoperative lamp.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.

MOT pass rates

How first tests ended, and how the pass rates are counted.

Passed first time: 80in every 100; Passed on the first test.
Fixed at the station: 3in every 100; Failed, then fixed at the test station the same day.
Failed: 17in every 100; Did not pass, and were not fixed at the test station.

First-attempt pass 79.6% of 1,531 first tests (2025): only cars that passed first time count. Official-style pass 83.0%: cars fixed at the test station also count as a pass. The 3 fixed and the 17 not fixed make the 20 in every 100 that did not pass first time.

Same model, other years

Passed first time in every 100, all tested in 2025.

Newer cars are younger, so look for a jump rather than the climb. A year earlier (2024), when these cars were a year younger, 82 in every 100 passed first time.

Year	Passed first time	First tests
2014	67 in every 100	532
2015	72 in every 100	552
2016	80 in every 100	1,141
2017	80 in every 100	3,012
2018	82 in every 100	2,469
2019 This car	80 in every 100	1,531

FAQs

Short answers about how to read this model-year guide.

Is the 2019 Kia Optima reliable?

The 2019 Kia Optima follows the pattern of the model years either side. Its main cause of failure was Tyre condition (rear), about 17 in every 100 failed tests. In 2025, 79.6% of 1,531 first MOTs on the 2019 Kia Optima passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 83.0%. Among 313 failed first-attempt MOT tests (test year 2025), Diesel engine warning light appears more often than on similar cars (10.2% of those tests; 32 observed failures; about 2.4× more often than similar cars). There is no single reliability score here; this is a pre-purchase checklist built from DVSA open data, not a guarantee for any individual car.

What is most likely to fail on a 2019 Kia Optima?

Ranked by how often they were actually recorded, the items that most often failed a 2019 Kia Optima at the first attempt were Tyre condition (rear) (16.6%), each as a share of the year's failed first attempts. That is what goes wrong most often on the car. The common faults table shows a different measure: faults that are unusual compared with similar cars.

What common MOT faults stand out on the Kia Optima 2019?

Among failed first-attempt tests we highlight patterns that appear more often than on similar cars. Top example: Diesel engine warning light (10.2% of those tests; 32 observed failures; about 2.4× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.

Why does Diesel engine warning light stand out?

Diesel engine warning light shows up more often than on similar cars (10.2% of those tests; 32 observed failures; about 2.4× more often than similar cars). That does not prove a design fault. Age, mileage, and how the car was used still matter. Treat it as a pre-purchase checkpoint, not a manufacturer service bulletin.

What are common problems with the 2019 Kia Optima?

Common MOT problem areas for the 2019 Kia Optima include Diesel engine warning light. These are the faults that stand out compared with similar cars, not a complete list of what can go wrong on any individual car.

What does this Kia Optima 2019 MOT report cover?

This page highlights MOT failure patterns for the 2019 Kia Optima (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.

Does this include engine and gearbox problems?

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.

2024 2025

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.
If the data for a car is too thin to say anything useful, we say so rather than guess.

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