Should I check the MOT history before buying a 1989 Mercedes 420 SE Auto?

Yes. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. A full MOT history analysis will highlight patterns that a single test result won't reveal.

What corrosion should I look for when inspecting a 1989 Mercedes 420 SE Auto?

Check brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that is expensive to fix and can fail an MOT.

How are tyres and brakes typically on a 1989 Mercedes 420 SE Auto?

Tyres and brakes are the most common advisory items on vehicles of this age. Budget for replacement if they are near the limit, and factor this into your offer price.

Do I need an HPI check when buying a 1989 Mercedes 420 SE Auto?

Yes. The MOT history will not show outstanding finance, insurance write-offs, or stolen status. An HPI check covers these areas and should be part of any used car purchase.

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Mercedes 420 SE Auto (1989)

118 real MOT outcomes analysed • 0.4% first-time pass rate

1989 Mercedes 420 SE Auto

CarHunch analysed 118 real MOT records for the 1989 Mercedes 420 SE Auto. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.

This 1989 Mercedes 420 SE Auto has a first-time MOT pass rate of just 40%, well below the UK average of 80%, which is a serious red flag for any potential buyer. None of the 117 petrol examples in this sample passed their MOT on the first attempt, and while dangerous defects are absent, the stark failure rate suggests these cars demand significant pre-purchase inspection and likely remedial work before use.

At an average mileage of 134,000 km for a 35-year-old car, these vehicles have been reasonably well-preserved, yet the pass rate collapse points to age-related deterioration rather than abuse. Before committing to purchase, have a trusted Mercedes specialist conduct a full pre-purchase inspection focusing on suspension, cooling systems, and electrical components—the typical failure points on W126-generation Mercedes of this era.

Below average reliability 79.6% below UK average

0.4%

pass MOT first time

UK average: ~80%

ever had a dangerous defect

recorded at any MOT

0.01

avg MOT failures per car

over 1 tests on record

What to check before buying a 1989 Mercedes 420 SE 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 Mercedes 420 SE Auto

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

Inspection

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Pass Rate by Fuel Type

Fuel type	Vehicles	Pass rate	Avg failures
Petrol (99%)	117	0%	0
Other (1%)	1	50%	1

MOT History Averages

Avg MOT tests per vehicle

0.01

Avg failures per vehicle

Avg advisories per vehicle

Found a specific Mercedes 420 SE Auto?

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

Other model years — Mercedes 420 SE Auto:

1986 1987 1988