2.2 Direct engine
In 2003 GM launched a new engine with direct fuel injection. The engine comes from the GM L61 engine family, also known as Z22SE but this time was installed a brand new direct injection system. Such system was introduced in 1999 by Siemens as a first European direct injection system. First time was applied in 1999 to the Renault IDE engines, after that in 2001 to the Citroen Peugeot 2.0HPI engines and Mercedes CGI engines.
The idea was good, but the execution was not entirely successful. The main reason was the poorly designed parts of the injection system, especially pressure regulators and high pressure pumps.
Of course, we know it now, but at the time when the system was introduced, designers were blazing unknown paths.
Engines with this injection system were withdrawn by Renault, Citroen and Mercedes in 2002/2003 due to constant technical problems. Opel, on the other hand, continued to try to improve the design.
Despite ongoing problems, it was only in 2009 that Opel improved the pressure regulators, which were the biggest problem because the malfunction even damaged diaphragm high pressure pumps.
Unfortunately, the high failure rate and service costs quickly spoiled the opinion about this engine. The answer of GN was the sale of cars in Japan (Subaru Traviq - badged Zafira) and Australia (Holden) and even Mexico and Porto Rico. To make it funnier, the same L61 engine was lunched in 2005 by Alfa Romeo in 2.2 JTS engines but equipped with Bosch direct injection system, it worked flawlessly with 185 HP.
Currently, we have a lot of solutions to improve this bad design, especially other types of pressure regulators and several models of high pressure piston pumps that can be used in these engines instead of very emergency diaphragm pumps
2.2 Direct engine specification
The Opel Vectra 2.2 Direct engine is a naturally aspirated petrol, 2.2 litre, double overhead camshaft 4 cylinder with 4 valves per cylinder. It produces 153 bhp (155 PS/114 kW) of power at 5600 rpm, and maximum torque of 220 N·m (162 lb·ft/22.4 kgm) at 3800 rpm.
The Siemens direct injection system is based on the first generation common rail injection system. The injection high pressure pump delivers fuel under high pressure to the injection rail. There is a pressure regulator on the rail that bleeds fuel to get the desired fuel pressure. The Z22YH injection system operates at a pressure from 40 bar during engine braking, 50 bar at idle to 110 bar at full load.
Advantages and disadvantages
The engine has many advantages, but also its disadvantages.
The advantages include:
- high torque at low revs, which has a positive effect on the dynamics without the need to screw the engine to high revs
- quite low fuel consumption as the engine is quite pleasant, you can easily achieve fuel consumption around 6.5l / 100km on the route, at speeds up to 120km / h. In the urban cycle, approx. 8.5 l / 100 km
- With an efficient fuel pressure regulator, the engine is practically failure-free and maintenance-free up to a mileage of approx. 200 thousand km, when it is necessary to replace the high pressure pump.
- Due to problems with engines, a large number of cars on the secondary market are in good technical condition with low mileage.
The disadvantages include:
- no possibility or difficult possibility to install LPG, which in some markets can be a serious disadvantage. Such installation is technically possible but not profitable.
- difficulties with car servicing resulting from the lack of knowledge of car repair shops about the drive unit, this also applies to the authorized Opel network
- high prices of injection system parts at authorized Opel workshops
Next generation of Opel direct injection engines
Since 2014, a whole family of direct injection engines with Bosch injection technology based on a single piston pump with an integrated throttle valve was created. It is a much more durable and economical solution.