BMW 420d M Sport Auto (2017)

240 real MOT outcomes analysed • 62% first-time pass rate

2017 BMW 420d M Sport Auto

CarHunch analysed 240 real MOT records for the 2017 BMW 420d M Sport Auto. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.

This 2017 BMW 420D M Sport has a first-time MOT pass rate of 62%, which is 18 percentage points below the UK average of 80%—a genuine concern for reliability. The good news is that dangerous defects are extremely rare (0%), and when failures do occur, they're infrequent at just 0.08 per vehicle on average.

These cars are running at a sensible 58,687 miles median for their age, so you're not looking at high-mileage examples, yet the poor pass rate suggests inherent mechanical vulnerabilities rather than wear-and-tear issues. Before committing to a purchase, budget for a thorough pre-buy inspection by a BMW specialist, as this cohort clearly needs closer scrutiny than most rivals.

Below average reliability 18% below UK average
62%
pass MOT first time
UK average: ~80%
58,687
typical mileage
46,845–69,983 middle half
0%
ever had a dangerous defect
recorded at any MOT
0.08
avg MOT failures per car
over 2.3 tests on record

What to check before buying a 2017 BMW 420d M Sport Auto

Practical pre-purchase checks for this age and model.

  • 📋 Check the full MOT history. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. Enter the reg below for a full AI analysis.
  • 🔍 Inspect for corrosion in person. Brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that's expensive to fix and can fail an MOT.
  • 🛞 Check tyres and brakes. The most common advisory items at this age. Budget for replacement if they're near the limit — factor this into your offer price.
  • 📄 Run an HPI check. The MOT history won't show outstanding finance, insurance write-offs, or stolen status — an HPI check will.

Before you buy a BMW 420d M Sport Auto

MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.

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Pass Rate by Fuel Type

Fuel type Vehicles Pass rate Avg failures
Diesel (100%) 239 61.8% 0.08
Gas Bi-Fuel (0%) 1 100% 0

Mileage Distribution

Most 2017 BMW 420d M Sport Auto vehicles sit in the blue band. If the car you're looking at is outside it, it's either unusually low or high mileage for its age.

46,845
low mileage
58,687
typical
69,983
high mileage

Half of all 2017 BMW 420d M Sport Auto vehicles fall between 46,845 and 69,983 miles.

2017 BMW 420d M Sport Auto — Still on the Road

Strong survival — 95 vehicles still getting MOTs in 2025, 97% of the peak.

68 95 2021 2025

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2021–2025.

MOT History Averages

2.3
Avg MOT tests per vehicle
0.08
Avg failures per vehicle
0
Avg advisories per vehicle

Found a specific BMW 420d M Sport Auto?

Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.

UK

Other model years — BMW 420d M Sport Auto:

2014 2015 2016 2018 2019