Pass rate
73.6%
Below average — 1.4 pts ahead of the 72.2% that cars this age and mileage manage.
Across 1,329 recorded tests.
Typical repair bill £61–£169
2004 MG Zs MOT pass rate
- 2004
- typical 87,422 mi
Check your postcode
Most common fault
Brakes
23.0% of faults · 20.9% nationally
mostly worn pads and discs, corroded pipes and a handbrake that will not hold.
Which year to buy
- Best 2024 96.9% pass
- Avoid 2003 70.4% pass
Across the 14 years on record, a spread of 26.5 points. See every year →
- First-attempt pass
- 67.2%
- Typical mileage
- 87k mi
The 2004 MG Zs MOT pass rate is 73.6% of its MOT tests — 1.4 points ahead of what its age and mileage predict. Brakes is the biggest single reason it fails, at 23.0% of what testers record.
Expert verdict
Body & chassis: 2.6× the national share
Body & chassis accounts for 14.6% of everything recorded on the 2004 MG Zs, against 5.6% nationally — 9.0 points above. Brakes are still the single largest share at 23.0%, but at 20.9% nationally that one is ordinary. Look underneath for corrosion near the jacking points and suspension mounts; surface rust is normal, flaking metal is not.
- When it fails, it costs. Only 22% of this model’s typical repairs come in under £30 in parts — the failures here tend to be the kind that need a garage rather than a bulb.
Written from this page's own figures: fault shares against the national composition, the like-for-like pass rate, and the priced repair list. How these are worked out
Watching a MG Zs? Get an email when these numbers change .
How does the 2004 MG Zs compare?
Cars of this age and mileage average 72.2%, so this figure is 1.4 points ahead of what its age and mileage predict. On a first attempt, before any retests, the figure drops to 67.2%. The median 2004 MG Zs in this dataset had covered 87,422 mi.
92% of the tests on this vehicle ran on Petrol, which passed 73.7% of the time. Pass rates also shift with the test month: tests recorded October–March passed 72.8% of the time, April–September 74.6%.
The single most recorded failure item is "Joints constant velocity boot severely deteriorated", noted on 7.07% of tests.
- 1,329 recorded tests behind this page.
- 73.6% overall pass rate, 67.2% on a first attempt.
- Across every year of the MG Zs, the average is 87.4% — best year 2024 (96.9%), worst 2003 (70.4%).
Figures count every completed test on this vehicle-year in the dataset, including retests. See methodology for the exact definition.
This page's data
- Tests analysed
- 1,329
- Typical mileage (median)
- 87,422 mi
- Make and model
- MG Zs
- Updated
- 2026-11-07
Source: DVSA anonymised MOT test data (2023–2025), OGL v3.0.
Top part to budget for
Body Panel Repair
Typically a garage job — get quotes before committing.
Does mileage affect the Zs MOT pass rate?
Pass rate by odometer reading. Bar lengths start at 61% so small gaps stay visible.
Fuel type and reliability
Pass rate by fuel type. Petrol is the most common here (92% of tests).
Where the MG Zs is most common
Across all Zs model years on record (2001–2024): 65,937 MG Zs cars tested in a recordable postcode area, across 122,759 tests. Cardiff (CF) has the most, with 2,874 cars tested there. Cars are counted by the postcode area of the MOT station, so this is where they were tested, not necessarily where their owners live.
| # | Postcode area | Cars | Pass rate |
|---|---|---|---|
| 1 | Cardiff (CF) | 2,874 | 83.1% |
| 2 | Swansea (SA) | 1,626 | 83.6% |
| 3 | Glasgow (G) | 1,575 | 82.8% |
| 4 | Newcastle upon Tyne (NE) | 1,476 | 86.3% |
| 5 | Birmingham (B) | 1,427 | 87.2% |
| 6 | Portsmouth (PO) | 1,279 | 87.4% |
| 7 | Peterborough (PE) | 1,160 | 88.1% |
| 8 | Sheffield (S) | 1,135 | 90.8% |
| 9 | Basildon (SS) | 1,097 | 93.2% |
| 10 | Chelmsford (CM) | 1,034 | 89.7% |
| 11 | Warrington (WA) | 1,031 | 90.7% |
| 12 | Preston (PR) | 993 | 90.4% |
| 13 | Bristol (BS) | 904 | 87.4% |
| 14 | Newport (NP) | 883 | 85.6% |
| 15 | Edinburgh (EH) | 865 | 83.1% |
| 16 | Paisley (PA) | 817 | 84.0% |
| 17 | Liverpool (L) | 811 | 88.5% |
| 18 | Gloucester (GL) | 808 | 87.8% |
| 19 | Southampton (SO) | 800 | 87.1% |
| 20 | Ipswich (IP) | 798 | 87.9% |
The twenty areas with the most MG Zs cars in the record, sorted by car count — sort the columns for a different question. Cars tested at a station whose postcode area could not be resolved are counted in the model's total but in no area, so the shares add up to slightly under 100% even across every area, and an area's cars are a subset of the model's. Pass rate is blank below 30 tests in an area, where a percentage is noise rather than a finding. How this model's pass rate varies by postcode →
Regional pass rates for the Zs
| Region | Tests | Pass rate |
|---|---|---|
| West Midlands | 256 | 72.3% |
| South East | 214 | 71.5% |
| South West | 181 | 70.7% |
| East of England | 165 | 74.5% |
| North West | 116 | 71.6% |
| East Midlands | 114 | 78.9% |
| Yorkshire | 97 | 76.3% |
| Scotland | 69 | 78.3% |
| North East | 52 | 76.9% |
| Wales | 49 | 71.4% |
| London | 16 | 81.3% |
Regions come from the postcode area recorded at the test station. Areas on region borders are assigned to the region with the majority of their population.
What fails a 2004 Zs
Everything a tester recorded on this vehicle, grouped into the inspection sections that produced it. The notch on each bar is the national share, so you can see at a glance whether this car is unusual or just ordinary.
A test can record several items, so these percentages do not add up to 100%. The exact strings, with prices, are in the full DVSA record at the bottom of this page.
Before your test
Three checks worth doing on a 2004 Zs
These are not generic tips — they are the faults recorded most often on this exact model, rewritten as things you can check yourself. All three take about ten minutes and cost nothing.
-
Check the suspension joints 5.3% of tests
“ball joint dust cover severely deteriorated”
With the car parked on level ground, rock the top of each front wheel in and out while someone watches the suspension arm. Clunks, or rubber boots split and greasy, are what testers record here.
-
Check corrosion 5.1% of tests
“component mounting prescribed areas prescribed area excessively corroded significantly reducing structural strength”
Look under the sills, around the jacking points and where the suspension mounts meet the body. Flaking, holed or crumbly metal fails; a brown stain on sound metal does not.
-
Check the lights 3.2% of tests
“headlamp lens slightly defective”
Switch everything on and walk round the car: both headlamps on dip and main, every indicator, both brake lights, reverse, fog and the two number-plate lamps. A bulb is a few pounds and a five-minute job.
Shares are the proportion of tests on this vehicle that recorded the item, so they overlap: one test can record several.
What it costs to get a 2004 Zs through its MOT
Across the 10 items that are recorded most often on this model, the average repair comes to £61–£169 — and 22% of those repairs are parts that cost under £30.
- Average repair across the 10 common items
- £61–£169
- Cheapest common item: srs malfunction indicator lamp warning lamp…
- £3–£12
- Dearest common item: component mounting prescribed areas…
- £180–£450
- Common items a careful owner can do at home
- 50%
- Repairs that still cost under £30
- 22%
Estimates from typical UK parts prices, weighted by how often each item appears in 1,329 MOT tests on this vehicle. They exclude diagnostics, retest fees and garage labour where the part is a DIY fit, and they are not figures from the DVSA dataset. Older and higher-mileage examples cost more than the average. How these estimates are built → · All MOT repair costs → · Cheapest cars to put through a test →
Every year of the Zs, side by side
14 model years on record, from 2001 to 2024. Across them the pass rate runs from 70.4% to 96.9% — a spread of 26.5 points. The bar under each year is the item that failed it most often.
- 2001 71.2% component mounting prescribed…
- 2002 72.6% ball joint dust cover severely…
- 2003 70.4% rbt (sp) efficiency below…
- 2004 73.6%joints constant velocity boot…
- 2005 75.3% ball joint dust cover severely…
- 2006 74.9% joints constant velocity boot…
- 2017 80.0% coil spring fractured or broken
- 2018 83.9% headlamp not working on dipped…
- 2019 85.5% headlamp not working on dipped…
- 2020 89.1% has a cut in excess of the…
- 2021 91.4% has a cut in excess of the…
- 2022 89.8% registration plate lamp(s)…
- 2023 91.9% registration plate lamp(s)…
- 2024 96.9% has a cut in excess of the…
Colour is the pass rate on a fixed scale, so a block means the same thing on any model. Each year links to its own page with the full fault breakdown.
Compare the 2004 MG Zs with another year
The raw pass rate mostly measures age. The year comparison adds the like-for-like figure, the mileage bands and the repair bill.
Other 2004 cars with a similar record
- Nissan Almera 73.5%
- Saab 9-3 73.5%
- Volvo S60 73.8%
- Volkswagen Lupo 73.8%
- Mercedes-Benz Clk 73.9%
- Suzuki Wagon-R+ 73.2%
Closest pass rates among 2004 cars with at least 2,000 tests, so a small sample cannot flatter itself into the list. See the full rankings: best and worst MOT pass rates.
The full DVSA record for the 2004 MG Zs 10 failure items · 6 advisories · 10 inspection categories · mileage brackets · all of it in the page, none of it above the fold
Every inspection category
Shares of the 3,559 individual items recorded on this vehicle, and the same share across all cars nationally. A single test can record several items, so a row is not a percentage of tests.
| Category | Items | This car | Nationally | Difference |
|---|---|---|---|---|
| Brakes | 831 | 23.00% | 20.89% | +2.11 |
| Suspension | 797 | 22.00% | 20.98% | +1.02 |
| Body, chassis, structure | 529 | 14.60% | 5.57% | +9.03 |
| Lamps, reflectors and electrical equipment | 422 | 11.70% | 12.21% | −0.51 |
| Tyres | 378 | 10.50% | 19.76% | −9.26 |
| Noise, emissions and leaks | 276 | 7.60% | 5.52% | +2.08 |
| Visibility | 119 | 3.30% | 4.97% | −1.67 |
| Non-component advisories | 95 | 2.60% | 4.18% | −1.58 |
| Seat belts and supplementary restraint systems | 69 | 1.90% | 0.82% | +1.08 |
| Steering | 43 | 1.20% | 2.57% | −1.37 |
The exact failure items, in the tester's words
| Recorded item | Severity | Tests | Est. cost |
|---|---|---|---|
| Joints constant velocity boot severely deteriorated Body, chassis, structure | Minor | 7.1% | £80–250 |
| Ball joint dust cover severely deteriorated Suspension | Minor | 5.3% | £18–45 |
| Component mounting prescribed areas prescribed area excessively corroded significantly reducing structural strength Suspension | Major | 5.1% | £180–450 |
| Joints constant velocity boot split or insecure, no longer prevents the ingress of dirt Body, chassis, structure | Major | 4.9% | £80–250 |
| Rbt (sp) efficiency below requirements Brakes | Major | 4.1% | £45–110 |
| Service brake performance excessively binding Brakes | Major | 3.3% | £60–150 |
| Headlamp lens slightly defective Lamps, reflectors and electrical equipment | Minor | 3.2% | £5–25 |
| Registration plate lamp(s) inoperative in the case of multiple lamps or light sources Lamps, reflectors and electrical equipment | Minor | 3.2% | £5–20 |
| Srs malfunction indicator lamp warning lamp indicates a fault Seat belts and supplementary restraint systems | Major | 2.5% | £3–12 |
| Exhaust system has a major leak of exhaust gases Body, chassis, structure | Major | 2.4% | £45–120 |
Severity is as recorded: Major and Dangerous fail the test outright; Minor and Advisory do not. Costs are estimates from typical UK parts prices — see how they are built.
What testers noted without failing the car
Advisories are the early warnings — the same parts a year or two before they fail. Reading them is how you tell a car that has been maintained from one that has been patched.
| Recorded item | Severity | Tests | Est. cost |
|---|---|---|---|
| Pins and bushes pin or bush excessively worn Suspension | Advisory | 15.8% | £40–150 |
| Rigid brake pipes excessively corroded Brakes | Advisory | 12.5% | £80–180 |
| Brake discs in such a condition that it is seriously weakened Brakes | Advisory | 11.4% | £45–110 |
| Tread depth below requirements of 1.6mm Tyres | Advisory | 11.2% | £45–95 |
| Has a tear, caused by separation or partial failure of its structure Tyres | Advisory | 10.2% | £45–95 |
| Engine oil leaks leaking excessively from engine Noise, emissions and leaks | Advisory | 9.8% | £200–700 |
Pass rate by mileage
| Mileage | Tests | Pass rate | Median odometer |
|---|---|---|---|
| 0-30k | 31 | 90.3% | 22,672 mi |
| 30-60k | 236 | 75.4% | 49,878 mi |
| 60-90k | 446 | 73.3% | 76,884 mi |
| 90-120k | 402 | 73.6% | 101,942 mi |
| 120k+ | 212 | 69.8% | 150,998 mi |
Source: 1,329 recorded tests on this vehicle-year. Every row above is recomputed from the same DVSA extract as the rest of the page — see the methodology.
2004 Zs MOT questions
What is the MOT pass rate for a 2004 MG Zs?
73.6% of the 1,329 2004 MG Zs tests in this dataset passed, against a national average of 72.2% for cars first used in 2004. First-attempt pass rate: 67.2%.
What are the most common MOT failures on a 2004 MG Zs?
The three most recorded items are joints constant velocity boot severely deteriorated (7.07%), ball joint dust cover severely deteriorated (5.27%), component mounting prescribed areas prescribed area excessively corroded significantly reducing structural strength (5.12%). Percentages are the share of tests on this vehicle that recorded the item.
Does mileage affect the 2004 MG Zs MOT pass rate?
Yes. Cars under 30,000 miles passed 90.3% of the time, falling to 69.8% for those over 120,000 miles. The median 2004 MG Zs in this dataset had covered 87,422 mi.
Which fuel type is most reliable for a 2004 MG Zs?
Petrol: 73.7% pass rate across 1,226 tests. Diesel: 72.4% pass rate across 98 tests. Shares are of the tests on this vehicle that recorded each fuel type.
Does the season affect the 2004 MG Zs MOT pass rate?
Tests recorded in the winter months (October–March) passed 72.8% of the time; summer months (April–September) passed 74.6%. Brakes, tyres and lights are tested harder in bad weather, but the difference is small on most models.