Electronic Diagnostics: Vauxhall Corsa C 1.7 DTI
Denso V5 management system.
Vauxhall’s diesel-powered Corsa is a popular vehicle and older examples are inexpensive to buy. But how do they fare from a diagnostic point of view? Kim Henson and Edward Haggar investigate.
In Britain, the history of the Vauxhall Corsa can be traced back to the rear-wheel drive Chevette of the 1970s (at that time the smallest model in the company’s line-up), with the front-wheel drive Nova hatchback effectively replacing it in 1983. For nonuk markets, the Nova was known as the Opel Corsa and, in terms of GM model designation, this was the Corsa A.
The Corsa B – far less angular in its bodywork than its predecessor – arrived in Britain in 1993, with the Nova name no longer being used. The restyled Corsa C made its debut in 2000 and was produced until 2006 (replaced by the Corsa D), with a mid-life facelift having been applied in summer 2003.
Engine choices included a range of Ecotec petrol units, with capacities ranging from 1.0 to 1.8 litres, plus 1.3- and 1.7-litre Isuzu diesel motors. Here we have a 2003 Isuzu dieselpowered Corsa C, with engine code DTH. A Denso V5 management system is employed.
Our guide to this model’s engine and its system is Edward Haggar.
The car’s VIN plate is helpful in terms of confirming details of the car you are working on. The VIN plate is found under the bonnet, on top of the righthand front suspension strut.
The Isuzu engine is incredibly easy to work on. They are known to be efficient, reliable units, and it is interesting to note that, in tweaked form, they are still employed in the latest Vauxhalls.
It is essential that the fuel passing through the injectors and engine is clean and free from contaminants. For this, the fuel filter needs to be renewed at least as often as specified by Vauxhall, preferably twice as frequently. The filter assembly is not shown separately in our close-up photographs, but is visible in our main engine bay photo, immediately adjacent to the coolant reservoir, towards the lefthand side of the engine bay.
The fuel filter assembly, which incorporates a Water In Fuel sensor, is secured by a single Torx T50 bolt at the
top. Always renew the seals together with the filter. If available, a primer pump is recommended for drawing fuel through the system following renewal of the filter. However, the job can be done without a primer pump – always fill the housing with diesel cleaner or neat diesel fuel, which does the trick.
A clean diesel system will enable the engine to perform at its best, and we recommend the ongoing use of a diesel cleaner at least once every month, as the
prevention of dirt build-up is better than a cure. Supermarkets such as Tesco, for example, sell Redex fuel system cleaners for about £2.50 per bottle.
The oil filter is not far down at the rear of the engine; the filter head requires a 36mm spanner. There is no particulate filter to worry about on these units.
The worst job on the Corsa, as well as other models in the Vauxhall line-up, is a clutch change – a nightmare if the subframe bolts have seized.
All references in our text and captions to ‘left’ and ‘right’ sides are from the point of view of someone sitting in the car and looking ahead. NOTES: