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Mazda RX-8 2003: MOT failure rate for its age

35.3% of 580 MOT tests of the Mazda RX-8 first registered in 2003 failed at the first attempt (2019–2024; retests excluded). Against this model's own normal rate at the same ages the index is 104.5 (95% CI 90.2–118.8; 100 = normal for this model at that age): the 2003 build year is no different from other years of the same model at the same age. This is a rough estimate from a smaller sample.

Mazda RX-8 built in 2003 at a glance
MeasureValueUnitCompared withYearsTests
Failed first time35.3%all ages tested2019–2024580
Index against this model at the same age (95% CI 90.2–118.8)104.5index100 = normal for this model at that age2019–2024580
Rank among this model's 8 build years6of 81 = fails least for its age2019–2024580
Tested in 202486testsmedian 66,478 miles202486
line · Mazda RX-8 built 2003 · first-time MOT failure share by age · built 2003 36.9% vs model normal 35.2% at age 17 · 2019–2024
Built 2003 against Mazda RX-8 normal for the age: first-time MOT failure share at each age, age 17: 36.9% vs 35.2%; age 18: 36.3% vs 34.5%; age 19: 32.3% vs 32.3%; age 20: 35.1% vs 32.5%; age 21: 25.6% vs n/a%. Axis from 0% to 40%. DVSA MOT bulk data, 2019–2024.

Data release dvsa-2024-v2 (24 Sep 2026) · page updated 30 Sep 2026 · full dataset (v5).

How does the 2003 Mazda RX-8 fail at each age?

Cars built in 2003 were tested at ages 17 to 21 between 2019 and 2024. Each row compares their first-time failure share with what this model normally shows at that age, after allowing for the overall failure level of each test year.

Mazda RX-8 built 2003: first-time MOT failure by age, against the model's normal rate at that age (2019–2024)
AgeTestsFailed, %95% intervalNormal for this model at that age, %Index (100 = normal)
17179 (rough estimate)36.930.1–44.135.2104.7
18157 (rough estimate)36.329.2–44.134.5105.4
19133 (rough estimate)32.325–40.732.399.9
20111 (rough estimate)35.126.9–44.432.5108.2
2186 (rough estimate)25.617.5–35.7not availablenot available

Source: DVSA MOT bulk data · Window: 2019–2024 · n = 666 (initial tests) · Method: normal rate = this model's first-time failure share at that age across its build years (cells of 400+ tests), adjusted for each test year's overall level; cells of 30+ tests, under 500 marked rough · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV

What fails most on the 2003 Mazda RX-8?

The most common failure group on cars built in 2003 is lamps, reflectors and electrical equipment: 24.6 items per 100 first tests, against 23.7 across all build years of the Mazda RX-8. These counts are not age-adjusted: cars built in 2003 were tested at ages 17 to 21.

Failure items per 100 first tests, Mazda RX-8 built 2003 against the Mazda RX-8 in all build years (2019–2024, not age-adjusted)
Failure groupBuilt 2003, per 100All build years, per 100Items
Lamps, reflectors and electrical equipment24.623.7164
Suspension2423.3160
Noise, emissions and leaks21.420.9143
Brakes17.115.7114
Body, chassis, structure13.56.190

Source: DVSA MOT bulk data · Window: 2019–2024 · n = 668 (initial tests of this build year) · Method: failure items grouped by DVSA's top-level defect groups, per 100 initial tests; groups with 30+ items · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV

How does 2003 compare with the years around it?

Among the 8 published build years of the Mazda RX-8, 2003 ranks 6 (1 = fails least for its age). 2004: index 104.8.

Mazda RX-8 build years: index against the model at the same age (2019–2024)
Build yearIndex (100 = normal)95% intervalVerdictTests
2003104.590.2–118.8no different (rough estimate)580
2004104.899.0–110.7no different (rough estimate)3,439
2005106.399.7–112.9no different (rough estimate)2,732
2006102.497.0–107.8no different (rough estimate)3,934
2007100.194.8–105.5no different (rough estimate)3,939
200891.785.0–98.3better (rough estimate)2,390
200979.570.8–88.2better (rough estimate)1,231
201076.259.3–93.1better (rough estimate)317

Source: DVSA MOT bulk data · Window: 2019–2024 · n = 18,562 (initial tests) · Method: observed failures against those expected for the same model at the same ages, test-year level adjusted; verdict follows the printed one-decimal bound · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV

How to cite this page

MOT Risk Index (2026). Mazda RX-8 2003 MOT statistics (data release dvsa-2024-v2; full dataset motriskindex-families-2024-v5, DOI 10.5281/zenodo.22975051), updated 30 September 2026. motriskindex.co.uk/cars/mazda-rx-8/2003/

How every figure is calculated: methodology. Age, test year and build year are tied together (age = test year − build year), so the test-year level is taken as observed, not estimated.

Other pages for this model

Mazda RX-8 2004 · Mazda RX-8 2005 · Mazda RX-8 2006 · Mazda RX-8 2007 · Mazda RX-8 2008 · Mazda RX-8 2009 · Mazda RX-8 2010 · Mazda RX-8 by postcode area · Mazda RX-8 body, chassis and structure failures · Mazda RX-8 brakes failures · Mazda RX-8 vehicle identification failures · Mazda RX-8 lamps, reflectors and electrics failures · Mazda RX-8 noise, emissions and leaks failures · Mazda RX-8 road wheels failures · Mazda RX-8 seat belts and airbags failures · Mazda RX-8 steering failures · Mazda RX-8 suspension failures · Mazda RX-8 tyres failures · Mazda RX-8 visibility failures