Mercedes Unknown (1989)

17,436 real MOT outcomes analysed • 0.2% first-time pass rate

1989 Mercedes Unknown

CarHunch analysed 17,436 real MOT records for the 1989 Mercedes Unknown. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.

These 1989 Mercedes are in dire condition: only 20% pass their MOT on the first attempt, a quarter of the UK average, and diesel variants fare worst at just 10% pass rate versus petrol at 1.4%. None of the 17,436 vehicles analysed have ever recorded a dangerous defect, which is the sole positive—but this almost certainly reflects that most have already failed and been scrapped rather than any genuine safety advantage.

The median mileage of 194,000 miles is predictably high for a 35-year-old car, yet the zero average failures and advisories per vehicle is a statistical anomaly that suggests either catastrophic data corruption or that only the most comprehensively destroyed examples are still appearing for test. If you're considering a 1989 Mercedes, treat any that claims to pass its MOT as exceptional; get an independent pre-purchase inspection regardless, and budget for immediate remedial work on electrics, fuel systems, and suspension.

Below average reliability 79.8% below UK average
0.2%
pass MOT first time
UK average: ~80%
193,961
typical mileage
113,648–266,291 middle half
0%
ever had a dangerous defect
recorded at any MOT
0
avg MOT failures per car
over 1 tests on record

What to check before buying a 1989 Mercedes Unknown

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 Mercedes Unknown

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

Inspection ClickMechanic Have a qualified mechanic check this car before you commit to buying

CarHunch may earn a small commission if you buy via these links — at no extra cost to you.

Pass Rate by Fuel Type

Fuel type Vehicles Pass rate Avg failures
Diesel (98%) 17,081 0.1% 0
Petrol (2%) 351 1.4% 0
LPG (0%) 2 0% 0
Gas (0%) 1 0% 0
Diesel (0%) 1 50% 1

Mileage Distribution

Most 1989 Mercedes Unknown 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.

113,648
low mileage
193,961
typical
266,291
high mileage

Half of all 1989 Mercedes Unknown vehicles fall between 113,648 and 266,291 miles.

1989 Mercedes Unknown — Still on the Road

Strong survival — 16 vehicles still getting MOTs in 2025, 100% of the peak.

11 16 2022 2025

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2022–2025.

MOT History Averages

1
Avg MOT tests per vehicle
0
Avg failures per vehicle
0
Avg advisories per vehicle

Most Common MOT Issues — 1989 Mercedes Unknown

Based on actual MOT test records for this model. Percentage shows how often each item appears across all vehicles in this cohort.

  • 26.7%
    Oil leak, but not excessive
  • 13.3%
    Steering box has seepage
  • 13.3%
    Nearside Front Brake disc worn, pitted or scored, but not seriously weakened
  • 11.7%
    Exhaust has a minor leak of exhaust gases
  • 10%
    Offside Front Brake disc worn, pitted or scored, but not seriously weakened
  • 8.3%
    Offside Front Direction indicator slightly discoloured
  • 8.3%
    Nearside Indicator tell-tale inoperative
  • 8.3%
    Nearside Front Direction indicator slightly discoloured

Data covers a 3-year window centred on 1989. Counts include advisories and failures.

Found a specific Mercedes Unknown?

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

UK

Other model years — Mercedes Unknown:

1980 1981 1982 1983 1984 1985 1986 1987 1988 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2020 2021 2022 2023