The 1.3 MultiJet is one of the smallest automotive diesel engines in the world. It was developed by General Motors engineers together with colleagues from Fiat. It is produced since 2003. Power range is from 75 to 105 hp.
The working volume of less than 1.3 liters, distributed over four cylinders, requires very precise fuel injection control. For this purpose, the fuel doses in each cylinder are divided into smaller portions. In the first copies, they were divided into 5 parts, and since 2009 (after modernization) – into 8 parts. This allowed to soften the engine operation and reduce the amount of harmful emissions in the exhaust gases.
The basic diesel engine of Fiat and Opel concerns was assembled in Polish Bielsko-Biala. It was the first unit to be produced at the Fiat-GM Powertrain joint venture in Poland. Today, the cooperation between the two companies is no longer so close, but engine production continues.
Most modifications of the engine are equipped with a turbocharger with fixed geometry, the most powerful – turbocharger with variable geometry. Diesel engines with a working volume of 1.3 liters went to a wide range of cars – from city cars to microcars. Since the power unit appeared under the emblem of various automobile brands, in each case it received a different name. Mostly MultiJet and CDTI, but also JTDM, DDiS, TDCi.
Technical characteristics of Z13DTH.
| Parameter | Characteristic |
|---|---|
| Precise volume | 1248 cm³ |
| Power system | Common Rail |
| Power | 90 hp |
| Torque | 200 Nm |
| Cylinder block | Cast-iron, in-line 4-cylinder (R4) |
| Cylinder head | Aluminum, 16 valves |
| Cylinder diameter | 69.6 mm |
| Piston stroke | 82 mm |
| Compression ratio | 17.6 |
| Engine features | Intercooler (intercooler) |
| Hydrocompensators | Yes |
| Transmission timing | Chain |
| Fasor regulator | No |
| Turbocharging | VGT (Variable Geometry Turbine) |
| Recommended oil | 3.3 liters, 5W-30 |
| Fuel type | Diesel |
| Environmental class | Euro 4 |
| Example service life | 330,000 km |
| Engine weight | 140 kg |
Typical problems
Given the rather complex design and often quite rough operation (the engine was usually used in service cars and small vans), the reliability of the motors should be rated highly. The low fuel consumption is also pleasing. City cars in real conditions sometimes consume only a little more than 4 liters/100 km.
Engines 1.3 Multijet / CDTI at high mileage are prone to increased oil consumption and compression drop, mainly when used in large and heavy models. The long change interval is particularly lethal for long-life class oil. Opel has defined an absolutely crazy 50,000 km for this, while Fiat limited itself to “only” 30,000 km. But even this is too much for a miniature diesel engine with a 3-liter lubricant reserve. In addition, under heavy loads, oil consumption increases. The oil level must be checked frequently, because a shortage of oil can cause the camshaft drive chain to jump.
The timing chain tensioner
The engine is very sensitive to even a small drop in engine oil level. Frequent travel in urban areas causes the oil level to drop significantly. If this is not noticed in time, the pressure in the system starts to decrease and, consequently, the tension of the chain. Lack of oil leads to improper operation of the chain tensioner. The chain can jump. For the same reason, you should not save money by buying cheap low-quality oil or delaying the date of its replacement. The consequences will prove too painful and expensive to fix. Chain tensioner in 1.3 CDTI/Multijet engine should be checked periodically for proper operation and replaced with a new one if necessary. As a rule, it does not last more than 70,000 km. In addition, in 1.3 Multijet engines there have been recorded problems with the timing chain drive and even chain breakage, which always ended in fatal damage.
The timing chain
There is a lot of contradictory information about the reliability of the timing chain of the 1.3 CDTI/Multijet engine. Someone calls this chain “bicycle”, indicating its fragility and tendency to stretch. Some report that this chain can survive several worn tensioners without stretching.
Leaks from under the thermostat
A small, but unnoticed in time coolant leakage can lead to overheating of the engine. It is necessary to regularly check the level of antifreeze in the tank.
Accelerated clutch wear
Too frequent aggressive driving and sloppy work with the clutch wear it out quickly.
Oil level increase
Owners of vehicles with a 1.3 CDTI/Multijet engine may find that the oil level in the crankcase has increased. This “miracle” occurs due to the dilution of oil with diesel fuel, which is abundantly fed into the combustion chambers during the procedure of burning the particulate filter. This filter is clogged during short city trips. The burning procedure is started at idle speed: the moment of burning can be determined by the exhaust and idle speed. That is, during the burn, the exhaust pipe emits smoke with a characteristic smell of plastic and the rpm rises to 1000. It is obligatory to wait for the end of burning and then turn off the engine. If you turn off the engine earlier, the fuel will get into the oil pan and dilute the engine oil. Generally, after several successful particulate filter burns, it is recommended to change the engine oil unscheduled. To achieve a natural and more gentle cleaning of the particulate filter, you should “walk” the engine 1.3 CDTI/Multijet in highway modes, driving at least 50 km at a constant high speed.
Soot filter
With frequent short trips the particulate filter of the 1.3 CDTI/Multijet engine gets clogged. The engine electronics can take into account the degree of clogging of this filter and, if necessary, starts its burning. It looks as follows. When stopping and working at idle speeds, all electrical consumers, including rear window heater and preheating plugs, are automatically turned on. This increases the load on the engine and, as a consequence, the engine temperature rises. Post-injection is activated. Due to this, the temperature of exhaust gases increases – the filter is burned. But not always this procedure is effective. And then the following symptoms appear: decreased acceleration dynamics, increased fuel consumption, acrid odor of unburned diesel fuel.
EGR valve and the problem with starting
Often owners of cars with 1.3 CDTI/Multijet engine face the following symptom: the engine starts and after a few seconds it stops. At the same time, computer diagnostics does not show any errors that could clearly indicate a problem. In this case, the EGR valve should be removed and cleaned. On this motor, the electrical (control) and mechanical parts of the EGR valve are separate. In dirty working conditions, the EGR valve simply jams in one position: its guide sleeve becomes contaminated with carbon deposits and soot, and the valve stops working. In this case, the electrical part of the EGR system does not see the problem, but fixes incorrect operation parameters, which causes the engine to stop.
Partial wedging of the EGR valve on a 1.3 CDTI/Multijet engine can cause a turbine operation error, although the true cause is not in it. The EGR valve regulates the amount of exhaust gases returned to the intake manifold. And if the valve is open, then at certain speeds the fuel-air mixture will be of the wrong composition and the exhaust gas output will be uncalculated. As a result, the electronics records a low turbine output error.
In some 1.3 CDTI/Multijet engines there were such failures as destruction of turbocharger blades and crankcase ventilation channel freezing (usually after a series of short trips in winter).
In general, despite the small displacement, the engine 1.3 CDTI/Multijet can be called survivable and unpretentious. It is able to pass up to 400,000 km without obvious wear of the piston. But such results can be achieved with proper operation. It is important to monitor the level and quality of engine oil, clean the intake manifold and allow the engine to “air out” on the highway.