MOT fail · manual section 6.1.2

Exhaust system has a major leak of exhaust gases

What this MOT fail means, how often testers record it and what the usual repair costs. From 130,233,413 DVSA MOT tests taken 2022 to 2025.

MOT data updated 28 September 2026

As a fail, per 100 MOTs (n=130,233,413)0.75

Most often at21 years

Times recorded971,701

Times recorded adds every DVSA code with this wording, so a test can record it more than once, for example on two wheels under separate codes.

What it means

This is a major defect: the car fails its MOT. A major defect may affect the car’s safety, put other road users at risk or harm the environment. The car fails its MOT and the defect must be repaired.

Before it reaches this point, testers often record it as an advisory: Exhaust system has a minor leak of exhaust gases.

The tester looks at the body and underside for corrosion and damage, especially near the points where suspension, steering and seat belts are mounted, and checks the exhaust, fuel system, drive shafts and towbar.

The MOT inspection manual describes the defect (section 6.1.2) as:

Exhaust system leaking or insecure

Read this section of the MOT inspection manual on GOV.UK

The DVSA codes counted on this page: the manual item and the defect text as DVSA records them. The heading above joins the two, as a certificate does; the tester also adds the position, such as nearside front.
Result	Manual item	DVSA defect text	Records
Fail Major	Exhaust system	has a major leak of exhaust gases (6.1.2)	971,701

Got an MOT advisory or defect on a certificate? Paste it into the MOT advisory checker to see what it means.

How common it is by age

Testers record it most at 21 years: 2.24 per 100 MOTs (n=1,321,417 tests at that age).

Per 100 MOT tests of cars at each age, all makes. We show no figure below 20 tests.
Age	Fail per 100	Tests (n)
3 years	0.008	8,016,463
4 years	0.018	8,699,937
5 years	0.051	9,425,360
6 years	0.11	10,382,720
7 years	0.18	10,537,318
8 years	0.30	10,440,457
9 years	0.45	9,949,012
10 years	0.63	9,049,507
11 years	0.81	8,087,514
12 years	1.02	7,303,151
13 years	1.22	6,612,160
14 years	1.44	6,054,526
15 years	1.64	5,591,675
16 years	1.80	4,858,625
17 years	1.90	4,040,458
18 years	2.02	3,261,622
19 years	2.12	2,479,858
20 years	2.18	1,845,952
21 years	2.24	1,321,417
22 years	2.23	913,980
23 years	2.20	619,531
24 years	2.17	428,815
25 years	2.13	313,355

Models that get it most

Each model generation is compared with cars of the same ages and fuel, so older and diesel models are not penalised for their age or fuel. Generations are never pooled.

Model generations with the highest rate as a fail, against cars of the same ages and fuel. A model’s figure counts this defect only at ages where it is among that model’s 25 most recorded items, and as zero elsewhere, so it is a floor. Tests (n) are all the generation’s MOT tests at ages with at least 1,000 tests each; at least 5,000 in total.
Model	Per 100 MOTs, at least	Same ages and fuel	Times as often	Tests (n)	Ages
Isuzu D-MaxIsuzu D-Max exhaust repair	2.99	0.18	16.8	134,777	3 to 13
Vauxhall CrosslandVauxhall Crossland exhaust repair	0.34	0.058	5.8	229,410	3 to 8
Chevrolet CaptivaChevrolet Captiva body and structure problems	3.91	0.69	5.6	25,550	9 to 16
Ford EcoSportFord EcoSport exhaust repair	0.78	0.18	4.3	402,494	3 to 11
Ford Pumafirst used 2019 or later	0.083	0.019	4.2	171,401	3 to 5
Vauxhall MokkaVauxhall Mokka exhaust repair	1.30	0.31	4.1	930,592	3 to 12
Citroen C3 AircrossCitroen C3 Aircross body and structure problems	0.27	0.068	4.0	110,010	3 to 7
Nissan PathfinderNissan Pathfinder body and structure problems	3.76	1.00	3.7	23,532	10 to 19
Isuzu TFIsuzu TF body and structure problems	2.42	0.66	3.6	6,237	11 to 14
Isuzu RodeoIsuzu Rodeo body and structure problems	3.62	1.07	3.3	18,681	12 to 19
Ford Transit ConnectFord Transit Connect exhaust repair	1.56	0.49	3.1	676,611	3 to 22
Vauxhall ComboVauxhall Combo exhaust repair	1.61	0.51	3.1	423,103	3 to 22
Mitsubishi Shogun SportMitsubishi Shogun Sport body and structure problems	5.00	1.58	3.1	18,439	16 to 21
Smart Forfourfirst used 2014 or laterSmart Forfour exhaust repair	0.91	0.30	3.0	89,645	3 to 10
Nissan NavaraNissan Navara exhaust repair	1.10	0.38	2.8	286,820	3 to 21
Toyota HiluxToyota Hilux exhaust repair	1.41	0.49	2.8	278,401	3 to 25
Fiat BravoFiat Bravo body and structure problems	4.61	1.65	2.7	20,980	12 to 17
Fiat DobloFiat Doblo exhaust repair Fiat Doblo body and structure problems	1.72	0.62	2.7	190,103	3 to 21
Hyundai Coupe	5.99	2.19	2.7	24,661	13 to 20
Peugeot 208Peugeot 208 exhaust repair Peugeot 208 body and structure problems	1.24	0.46	2.7	809,087	3 to 13

Read this with care. A fail rate is not a measure of build quality. How far cars are driven, how they are used and how well owners maintain them all change it, and wear items such as tyres and brake pads are common fails. Compare a model only with cars of the same age. Methodology and limits.

Repair and cost

The usual repair is exhaust repair.

Median price (80 shops)£212.09

Middle half of prices£182.35 to £263.41

ONS price quotes for “EXHAUST FITTING FAST FIT”, September 2025 to August 2026, UK, 1,020 quotes from 80 shops. The ONS item is an exhaust fitted at a fast-fit centre; which part of the exhaust is not stated. Consumer prices as quoted.

If a garage also charges labour

Local garage labour, per hour (65 shops)£78

Local garage, middle half£70 to £96

Main dealer labour, per hour (62 shops)£156

Main dealer, middle half£144 to £174

Median hourly rate charged for car repairs, from 1,058 local garage and 953 main dealer price quotes collected by the ONS, September 2025 to August 2026. The same shops are priced each month, so the number of shops is the real sample.

Exhaust repair: cost and the models that need it more often

Related MOT defects

All body, structure and attachments defects All MOT defects Car repair costs

Buying a used car?

These figures describe all cars, not any one car. Found one you might buy? See what the VetTheCar Buying Report would tell you.

See an example report MOT fail rates by model All free tools

Source

Contains public sector information licensed under the Open Government Licence v3.0. Source: DVSA anonymised MOT test data, class 4 normal MOT tests, 2022 to 2025, and the MOT inspection manual published on GOV.UK. Prices: ONS consumer price inflation price quotes, September 2025 to August 2026, UK.

MOT data updated 28 September 2026. Prices updated 22 September 2026.

Not affiliated with or endorsed by DVSA or the Office for National Statistics. How we calculate these figures · Data sources