MG

MG Zs (2003)

5,323 real MOT outcomes analysed • 72.2% first-time pass rate

2003 MG Zs

CarHunch analysed 5,323 real MOT records for the 2003 MG Zs. Real test outcomes — pass rates, defect profiles, mileage data — from verified DVLA records. Updated as new MOTs are recorded.
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On this page
AI Analysis Reliability Overview Common Issues Check a Specific Reg Petrol vs Diesel Buyer's Checklist Pass Rate by Fuel Mileage Distribution Still on the Road MOT Averages Colour Breakdown Compare Models

The 2003 MG ZS struggles to match the UK average, with a first-time pass rate of 71.7% against the national 80%—and that's a red flag made worse by the fact that nearly 3 in 10 of these cars (29.1%) have been flagged for dangerous defects during their MOT history. Petrol and diesel variants perform almost identically, both around 71%, so fuel choice won't improve your odds.

These cars are now over 20 years old and averaging 63,000 miles, which is reasonable, but the real concern is what inspectors find: each vehicle racks up an average of 3.86 failures and 15.4 advisories per test, suggesting systemic durability issues rather than isolated problems. If you're considering one, have a pre-purchase inspection done by someone who knows these cars well, and budget for repair costs—the MOT history indicates this model demands more upkeep than most of its peers.

The 2003 MG Zs has a below-average first-time pass rate (72.2% vs ~80% UK average) — check the specific vehicle's full MOT history carefully before buying.

⚠️ Over 1 in 5 of these vehicles have had a dangerous MOT failure at some point — usually tyres or brakes, and often a one-off issue rather than a persistent problem. The group stats won't tell you which one you're looking at.
First-time pass
72.2%
UK average ~80%
Below average
Dangerous (ever)
29.1%
At least once in MOT history
Check this vehicle
Avg failures / car
3.86
Over 13 tests on record
High
Typical mileage
58k
Middle half: 45k–72k
For context
⚠️ Below average. More vehicles in this cohort fail their first MOT than typical. Scrutinise this vehicle's history — look for recurring issues, not just the latest result.
🔧 Expect consumable spend. An average of 15.4 advisories per vehicle tells you wear items (tyres, brakes) get flagged regularly. Budget for them — they're not surprises.
🔍 The dangerous defect figure is real. Most are one-off tyre failures or brake issues — not structural problems. But it's exactly why checking the individual vehicle's history is essential, not optional.

These stats describe 5,323 vehicles as a group. The specific vehicle you're looking at could be the one good example or the one outlier. Run its registration to find out.

Buyer beware — pass it on

What tends to go wrong

Across 5,323 vehicles — figures show how many had each issue flagged at least once in their MOT history.

Brake wear 71.5%
Parking brake: efficiency below requirements · Front Brake pad(s) wearing thin · Parking brake: parking brake efficiency only just met. It would appear that the braking system requires adjustment or repair. · …
Ask the seller when brakes were last serviced. If they don't know, factor in the cost.
Tyre wear 68.8%
Nearside Front Tyre worn close to the legal limit · Offside Front Tyre worn close to the legal limit · Nearside Rear Tyre worn close to the legal limit · …
Budget for a full set — on a vehicle this age, tyres are expected consumables. An inspection will confirm how much is left.
Other issues 33%
Oil leak · Child seat fitted not allowing full inspection of adult belt · Windscreen has damage to an area less than a 40mm circle outside zone 'A'
Lighting 21.8%
Offside Stop lamp not working · Nearside Stop lamp not working
Usually cheap to fix. Worth confirming all lights work before collecting.

Data covers a 3-year window centred on 2003.

See this vehicle's full MOT history & AI hunches

Spot recurring advisories, hidden issues, and how it compares to 5,323 MG Zs cars.

UK

Petrol vs Diesel

Pass rate difference of 2 percentage points — worth knowing if you're choosing between the two.

72.4%
Petrol
4,603 vehicles
70.4%
Diesel
704 vehicles

Before you buy a 2003 MG Zs

Based on MOT data from 5,323 vehicles — here's what to check.

  • 📋 Check the full MOT history. 29.1% of these vehicles have had a dangerous defect recorded - recurring advisories often signal problems years before they become failures.
    Search the reg on CarHunch for the full MOT history, reliability stats and a free AI-powered analysis of that exact vehicle.
  • 🔍 Brake pipes, sills and subframes are the key areas on a vehicle this age — structural rust is hard to spot without getting underneath. A mechanic will check all of this before you commit, and give you a concrete basis to negotiate on price. Inspection ClickMechanic
  • 📄 Outstanding finance, insurance write-offs and clocking won't appear in the MOT records — a dedicated history check covers all of this. Our link gets you 20% off automatically. History carVertical Get 20% off via CarHunch

Pass Rate by Fuel Type

Fuel type Vehicles Pass rate Avg failures
Petrol (86%) 4,603 72.4% 3.82
Diesel (13%) 704 70.4% 4.2

Colour Breakdown

Based on 38,683 MG Zs vehicles registered in the UK — across all years. From DVLA registration records.

Blue 26.7%
10,339
Red 16.9%
6,551
Silver 13%
5,028
White 11.9%
4,615
Grey 11.6%
4,470
Black 10.4%
4,019
Green 5.1%
1,962
Orange 2.5%
951
Yellow 1.9%
737
Turquoise 0%
6
Purple 0%
5

Mileage Distribution

Most 2003 MG Zs vehicles sit in the blue band. If the vehicle you're looking at is outside it, it's either unusually low or high mileage for its age.

57,982
typical
44,877
low mileage
71,865
high mileage

Half of all 2003 MG Zs vehicles fall between 44,877 and 71,865 miles.

Is the mileage you're seeing normal?
Under 44,877 miles — lower than most. Could be great, or could be a vehicle that rarely moved. Check test frequency and mileage progression in the MOT history.
44,877–71,865 miles — normal for age. This is where most 2003 MG Zss sit.
Over 97,017 miles — higher than typical. Not necessarily a problem, but check service history and look out for advisory build-up on tyres and brakes.

2003 MG Zs — Still on the Road

Numbers are thinning — 8% of 2003 MG Zss are still active.

Numbers are declining — 226 vehicles still getting MOTs in 2025 (8% of peak).

2,906 226 2014 2025

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2014–2025.
* The 2020 dip reflects the government's COVID-19 MOT exemption, which allowed certificates to be extended by six months — fewer tests were conducted that year.

MOT History Averages

13
Avg MOT tests per vehicle
3.86
Avg failures per vehicle
15.4
Avg advisories per vehicle
Other model years — MG Zs: All Zs years → Which year to buy? →
2001 2002 2004 2005 2006 2017 2018 2019 2020

Or browse all models: MG →

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Compare with another model

See how the 2003 MG Zs stacks up against a rival.

Buyer beware — pass it on