MERCEDES UNCLASSIFIED (1991)
Running costs, common problems, and reliability data based on 33 real MOT tests in 2024.
MOT Pass Rate
73%
Total Tests (2024)
33
Avg Mileage
102,932 mi
Est. Annual Cost
£2,050
Is the 1991 MERCEDES UNCLASSIFIED reliable?
Average reliability. Expect some repairs as it ages. That's 9 points below the national average of 82%. It falls below the MERCEDES brand average of 87%.
At 33 years old, 73% of MERCEDES UNCLASSIFIEDs from 1991 passed their MOT first time in 2024. That's based on 33 tests across the UK. The average mileage at this age is 102,932 miles.
How does the 1991 MERCEDES UNCLASSIFIED compare?
Mileage Analysis
The average 1991 MERCEDES UNCLASSIFIED has 102,932 miles on the clock, which is significantly below the expected 244,200 miles for a 33-year-old car. Low-mileage examples may have spent time sitting unused, so check for issues like corroded brakes or perished rubber seals.
Best year to buy a MERCEDES UNCLASSIFIED?
The most reliable year is the 2021 model with a 96% MOT pass rate, while the 1997 model has the lowest at 66%. The 1991 sits between the two at 73%.
How much does a 1991 MERCEDES UNCLASSIFIED cost to run?
Higher than average due to low pass rate
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT pass rate data. Insurance not included.
MERCEDES UNCLASSIFIED by Year
| Year | Pass Rate | Tests | Avg Mileage |
|---|---|---|---|
| 2021 | 96% | 270 | 14,108 mi |
| 2020 | 93% | 237 | 17,059 mi |
| 2019 | 95% | 176 | 25,080 mi |
| 2018 | 92% | 202 | 40,291 mi |
| 2017 | 91% | 200 | 39,620 mi |
| 2016 | 87% | 326 | 45,907 mi |
| 2015 | 91% | 252 | 72,531 mi |
| 2014 | 86% | 289 | 83,046 mi |
| 2013 | 89% | 245 | 52,132 mi |
| 2012 | 89% | 185 | 66,863 mi |
| 2011 | 90% | 126 | 63,066 mi |
| 2010 | 92% | 98 | 94,655 mi |
| 2009 | 79% | 174 | 100,957 mi |
| 2008 | 79% | 354 | 111,482 mi |
| 2007 | 81% | 259 | 105,351 mi |
| 2006 | 81% | 240 | 95,112 mi |
| 2005 | 79% | 273 | 101,492 mi |
| 2004 | 79% | 298 | 91,119 mi |
| 2003 | 73% | 178 | 102,840 mi |
| 2002 | 84% | 214 | 129,941 mi |
| 2001 | 73% | 107 | 121,123 mi |
| 2000 | 73% | 195 | 116,472 mi |
| 1999 | 78% | 223 | 144,511 mi |
| 1998 | 81% | 155 | 139,571 mi |
| 1997 | 66% | 65 | 104,116 mi |
| 1996 | 66% | 101 | 175,170 mi |
| 1995 | 78% | 45 | 212,804 mi |
| 1994 | 74% | 86 | 85,110 mi |
| 1993 | 89% | 47 | 159,142 mi |
| 1992 | 60% | 40 | 117,020 mi |
| 1991 | 73% | 33 | 102,932 mi |
| 1990 | 83% | 58 | 95,507 mi |
Checking a specific MERCEDES UNCLASSIFIED?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 1991 MERCEDES UNCLASSIFIED
The 1991 MERCEDES UNCLASSIFIED is a performance with a 5958cc diesel engine. 33 of these vehicles were MOT tested in 2024, making it a rare model on UK roads. It sits in the bottom 78% of 1991 cars for MOT pass rates.
With an average of 102,932 miles at 33 years old, MERCEDES UNCLASSIFIED owners tend to use this car less than the typical driver. Very low mileage could mean the car has been garaged or used only for short trips, which can cause its own issues like battery drain and moisture buildup.
1991 MERCEDES UNCLASSIFIED Fuel Costs
The 5958cc diesel engine is on the larger side, so fuel won't be this car's strong point. Expect around 40 mpg in mixed driving, which works out to roughly £1,245 per year at current diesel prices of 148p per litre (based on 7,400 miles per year). Diesel cars of this age should have their DPF (diesel particulate filter) checked, as replacements can be costly.
What does it cost to own a 1991 MERCEDES UNCLASSIFIED?
Total estimated annual running cost is £2,050 (£171/month), broken down as £1245 fuel, £250 road tax, £55 MOT, and £500 predicted repairs. Repair costs are moderate, reflecting the 73% pass rate. Keeping on top of servicing will help avoid surprises.
MERCEDES UNCLASSIFIED Reliability Trend
Newer MERCEDES UNCLASSIFIEDs show better MOT pass rates than older ones, with an average improvement of 13 percentage points.
Buying a Used 1991 MERCEDES UNCLASSIFIED
At 33 years old, the MERCEDES UNCLASSIFIED is firmly in budget territory. Purchase prices are low, but check for rust, worn suspension bushes, and electrical gremlins. A full service history is especially valuable at this age. If you're flexible on year, the 2021 model has the highest pass rate at 96%. Note: with only 33 tests in our data, these figures should be treated as indicative rather than definitive.