1979 Jaguar Xj12 MOT Pass Rate
Pass rate for Xj12 models manufactured in 1979, based on 45 real MOT test results.
Data from official DVSA MOT testing records
1979 Jaguar Xj12 MOT Analysis
The 1979 Jaguar Xj12 has an MOT pass rate of 82.2% based on 45 tests — well above the UK average for UK vehicles. Cars of this vintage present for MOT with an average of 36,569 miles on the odometer. With a 17.8% failure rate, the 1979 Xj12 is rated as "Excellent" for MOT reliability.
The leading cause of MOT failure for the 1979 Jaguar Xj12 is Exhaust, Fuel and Emissions, responsible for 2.2% of failures. Emissions failures occur when exhaust gases exceed legal limits for carbon monoxide (CO), hydrocarbons (HC), or particulate matter (diesel). Common causes include faulty oxygen sensors, clogged catalytic converters, or DPF issues on diesel vehicles. Typical repair costs range from £100–1,000+. Suspension is the second most common issue at 2.2%.
Top failures specific to 1979 models only. The overall Xj12 page may show different rankings.
What Fails Most
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Exhaust, Fuel And Emissions | 2.2% | 1 |
| 2 | Suspension | 2.2% | 1 |
Failures per 10,000 Miles
avg. 36,569 miFor every 10,000 miles driven, this shows what percentage of MOT tests fail for each category. This accounts for how far cars are actually driven, not just raw pass/fail counts.
View as table
| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Emissions & Exhaust | 0.61 | 2.2% | 1 |
| Suspension | 0.61 | 2.2% | 1 |
Mileage Statistics
Mileage-adjusted failure rate — accounts for how much this model year is typically driven.
About This Data
The 1979 Jaguar Xj12 has an MOT pass rate of 82.2% based on 45 tests — well above the UK average for UK vehicles. Cars of this vintage present for MOT with an average of 36,569 miles on the odometer. With a 17.8% failure rate, the 1979 Xj12 is rated as "Excellent" for MOT reliability.
If you own or are considering buying a 1979 Jaguar Xj12, you can expect reliable MOT performance overall. Before your MOT, pay particular attention to exhaust, fuel and emissions: If the engine management light is on, get it diagnosed before the MOT. For diesel cars, ensure the DPF has completed a regeneration cycle. Regular servicing and using premium fuel before the test can help. With relatively low average mileage of 36,569 miles, many of these vehicles are still in good mechanical condition.
Exhaust, Fuel and Emissions — 2.2% of failures
Exhaust, Fuel and Emissions issues account for 2.2% of MOT failures on 1979 Jaguar Xj12 models. Emissions failures occur when exhaust gases exceed legal limits for carbon monoxide (CO), hydrocarbons (HC), or particulate matter (diesel). Common causes include faulty oxygen sensors, clogged catalytic converters, or DPF issues on diesel vehicles. Typical repair costs: £100–1,000+. Pre-MOT check: If the engine management light is on, get it diagnosed before the MOT. For diesel cars, ensure the DPF has completed a regeneration cycle. Regular servicing and using premium fuel before the test can help.
Suspension — 2.2% of failures
Suspension issues account for 2.2% of MOT failures on 1979 Jaguar Xj12 models. Suspension failures typically involve worn bushes, leaking shock absorbers, broken coil springs, and damaged suspension arms. These affect ride quality, tyre wear, and road holding. Typical repair costs: £200–500. Pre-MOT check: Look for uneven tyre wear, listen for clunking over bumps, and check if the car pulls to one side. A bouncy ride suggests worn shock absorbers. Visually inspect coil springs for cracks.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.