The most reliable cars of 2010

Every 2010 car tested in Britain in one year, ranked by how often it failed. Measured, not surveyed.

Best

#	Car	Engine	Failure rate	Tests
1	Porsche 911	3.8 Petrol	6%	1,008
2	Porsche 911	3.6 Petrol	7%	724
3	Bentley Continental	6.0 Petrol	8%	578
4	BMW M3	4.0 Petrol	9%	651
5	Toyota Estima	2.4 Hybrid	11%	780
6	Nissan 370 Z	3.7 Petrol	12%	688
7	Fiat Ducato	2.3 Diesel	12%	2,017
8	BMW 1 Series	3.0 Petrol	13%	508
9	Peugeot Boxer	2.2 Diesel	13%	2,167
10	Fiat Ducato	3.0 Diesel	14%	947
11	Lexus IS250	2.5 Petrol	14%	1,345
12	Porsche Cayenne	3.0 Diesel	14%	658
13	BMW Z4	3.0 Petrol	14%	761
14	Jaguar XKR	5.0 Petrol	15%	995
15	BMW 7 Series	3.0 Diesel	15%	764
16	Toyota RAV-4	2.0 Petrol	15%	689
17	Audi Q7	3.0 Diesel	15%	1,657
18	Toyota IQ	1.3 Petrol	15%	810
19	Toyota Estima	2.4 Petrol	16%	825
20	Mazda MX-5	2.0 Petrol	16%	2,702
21	Toyota IQ	1.0 Petrol	16%	3,658
22	Ford Focus	2.5 Petrol	16%	3,412
23	BMW Z4	2.5 Petrol	16%	1,569
24	Fiat Ducato	2.2 Diesel	16%	980
25	Honda CR-V	2.0 Petrol	16%	5,940

Worst

#	Car	Engine	Failure rate	Tests
1	Nissan Primastar	2.0 Diesel	34%	671
2	Vauxhall Vivaro	1.9 Diesel	34%	1,467
3	Nissan Qashqai	1.5 Diesel	34%	25,064
4	Nissan Qashqai	2.0 Diesel	33%	2,890
5	Renault Clio	1.5 Diesel	33%	7,797
6	Renault Grand Modus	1.5 Diesel	33%	663
7	Renault Kangoo	1.5 Diesel	33%	6,019
8	Vauxhall Vivaro	2.0 Diesel	33%	8,213
9	Renault Megane	1.5 Diesel	32%	9,990
10	Mitsubishi Lancer	2.0 Diesel	32%	1,307
11	Ford Transit	2.2 Diesel	32%	21,982
12	Renault Grand Scenic	1.6 Petrol	32%	574
13	Renault Megane	1.9 Diesel	32%	1,360
14	Ford Transit Connect	1.8 Diesel	32%	7,527
15	Renault Trafic	2.0 Diesel	32%	7,641
16	Nissan Juke	1.5 Diesel	32%	889
17	Chevrolet Aveo	1.2 Petrol	32%	1,701
18	Renault Grand Scenic	1.5 Diesel	31%	4,949
19	Chevrolet Captiva	2.0 Diesel	31%	2,477
20	Citroen DS3	1.6 Diesel	31%	3,072
21	Renault Megane	1.6 Petrol	31%	10,372
22	Mazda 5	1.8 Petrol	31%	664
23	Peugeot 5008	1.6 Diesel	31%	2,157
24	Ford C-Max	1.8 Diesel	31%	1,546
25	Vauxhall Combo	1.7 Diesel	31%	1,786

What this measures

Britain tests every car over three years old against a published standard and publishes the result. This is that record for the 2010 model year, so every car here is the same age and none is flattered by being newer.

A car driven less fails less. An expensive one often sits high for reasons that are not about how well it was built, which is why the app can rank these at the same odometer reading.