This engine was first produced in 1990. Since then, it underwent a significant number of changes until its final retirement in 2014. The main milestones of modernization were associated with a change in the type of fuel system used. This material will consider the main features of this engine, as well as the most common breakdowns.
Immediately it should be noted that it is the first version of the engine, where Common Rail injection was used, that will be considered.
In 2003, one of the most important transitions in the life cycle of this engine took place, the DTI engine became CDTI. At that moment, two versions of the new engine appeared at the same time, the differences of which were in the fuel system used. Each of the engines was intended for certain cars. The manufacturers of fuel systems were the company Bosch and the company Denso. Each of the engine versions differed in certain design features, principles of structure of some components, as well as the size of the units. Both engines had the same index – Z17DTH, as well as the power of 100 hp. However, there was a version of the engine with a capacity of 80 hp. In 2007, another important modernization of the engine would take place, it would be fitted only with the Denso fuel system, which was considered to be more progressive and innovative.
At the same time, engines could also be further categorized based on the type of turbines used, the firmware, and a host of other smaller factors.
An engine designed to work with one fuel system could not be utilized with another due to the difference in attachments as well as many additional components.
Opel Z17DTH 1.7 CDTi motor specifications
| Characteristics | Parameter |
|---|---|
| Exact volume | 1686 cm³ |
| Power system | Common Rail |
| Engine power | 101 hp |
| Torque | 240 Nm |
| Cylinder block | Cast iron, R4 |
| Cylinder head | Aluminum, 16 valves |
| Cylinder diameter | 79 mm |
| Piston stroke | 86 mm |
| Compression ratio | 18.2 |
| Engine Features | Intercooler |
| Hydrocompensators | No |
| Transmission timing | Belt drive |
| Fasoregulator | No |
| Turbocharger | VGT |
| Oil | 5.0 liter 5W-30 |
| Fuel type | Diesel |
| Environmental class | Euro 4 |
| Example service life | 400,000 km |
| Engine weight | 170 kg |
Opel Z17DTH 1.7 CDTi engine is a compact diesel engine with VGT turbocharger and intercooler, known for its reliability and durability.
Differences in engine design
In order to accurately identify the engine in front of you, you need to pay attention to the injectors and fuel lines. The key difference here is the injector plugs, or rather their location. At Bosch they are located facing the driver’s seat, and at Denso – to the right front wheel arch. Due to this feature, you can easily classify a particular engine.
Another significant difference is the valve covers. For example, the engine with Denso has a hatch turned to the other side. Upon closer inspection, there are a number of other factors that can uniquely identify a particular type of fuel system and engine. Each of these factors is due to the design features of the high-pressure fuel lines.
The labeling of control units also differs. Fastening of the Denso fuel injector implies the use of two bolts, while in the case of Bosch – three. There are many other small differences, among which are: the length of timing belts, sensors, lobes of camshaft sensors. Despite all these differences, it is worth noting that both engines have the same crankshafts.
Main problems of the 1.7 CDTI engine
When discussing the main problems of this engine, we will consider its very first variant, the engine (Z17DTL) with an output of 80 hp, which was removed from the Opel Astra in 2004. This engine has a fairly large resource capacity, reliability and endurance, but like any unit has certain problematic points, which will be discussed below.
Crankshaft position sensor
In most cases, all breakdowns are reduced to the faulty operation of this sensor. The main signs are unstable engine operation, it stalls on the move, as well as extremely problematic to start hot. The problem will disappear in those moments when the sensor will warm up sufficiently.
Engine Control Unit
Another problematic node in the car. Its constant malfunctions are associated with an unfortunate location, since it is located in front of the front left wheel in the arch. Because of this, it is heavily contaminated, exposed to dirt and dust. This leads to unstable operation of the component and the engine will stall. In some cases, it is possible to repair the unit, but its replacement will also be relatively cheap.
Generator
The generator also refers to problematic devices in the car, but for the most part this is due to the location of the vacuum pump next to it. The peculiarity of the functioning of the device is that the pump is constantly lubricated with oil, but over time the oil seal installed in it wears out, because of which the oil begins to drip onto the diode bridge. This causes the diodes to overheat and the alternator to shut down. As soon as the diode cooling occurs – the normal functioning of the system will be restored.
Vacuum pump
This pump creates vacuum pressure for the functioning of the most important components of the car – brakes and electro-vacuum valves. Each of these components has a separate line to which the vacuum is distributed. It is very easy to distinguish between them, as the brake line connection is smaller than the valve connection.
heat exchanger
The main problem occurs with the gasket in the heat exchanger, which due to wear loses its own flexibility, which leads to oil leaks. It begins to mix with antifreeze, and if this process is not stopped in time, the oil will corrode all the pipes in the cooling system.
Turbine
The engine 1.7 CDTI with an output of 80 hp is equipped with a Mitsubishi TD025 turbine. It should be noted that this turbine has a fairly high reliability. At high mileage it starts to leak oil into the inlet.
EGR valve
In fact, the EGR valve rarely causes problems to Opel drivers, but in some cases it can also affect the car’s performance. For example, if you notice that when accelerating the car there are strong vibrations or a sharp drop in traction, then you should pay attention to this valve. It is enough to remove and clean it. This will lead to a significant increase in the power of the car.
Fuel system
The Bosch pump is characterized by high reliability, and the only common reason that leads to its replacement is that the pump ceases to create a sufficient level of pressure in the fuel ramp, which manifests itself in a stalled engine when trying to start it. You can check the pressure level, as well as the dynamics of its change with the help of diagnostic software. It allows to determine quite accurately the dynamics of pressure changes at different stages of engine operation.
Another advantage of Bosch injectors is the fact that they are repairable, and any repair is relatively inexpensive.
Injector liners
In this engine, all injectors are mounted using special steel liners where o-rings are specially fitted to seal the cooling channel. Over time, these rings get tanned, causing oil to start leaking into the antifreeze. In very rare and neglected cases, antifreeze will enter the cylinders.
If you pay attention to the factory requirements for maintenance, then the replacement of rubber rings of the liners is required to be carried out every time the injectors are removed, but in practice, rarely anyone adheres to such a recommendation. The problem here is the high labor intensity of such a process, because of which many car owners do not want to mess with this unit.
Problems with liners can also form in the case of improper removal of injectors. Any work with liners should be carried out by professionals, because it is extremely important to keep them pressed. In the case of any work on their removal, the subsequent installation involves pressing.
Oil pump
The main problem is not in the pump itself, but in the oil seals, which over time lose their properties and begin to leak oil. In this case, leaks are quite common. The main danger of such a leak is the lubrication of the belt, because of which it can slip or jump.