Diesel Engine Designations: TDI, HDi, JTD. Do you know them all?
In the automotive world, we come across countless abbreviations, including the designations of diesel engines. Some designations of diesel engines are quite similar, so it is not surprising that many people are not familiar with them.
For this reason, we decided to prepare a list of the most common diesel engine designations, in which we will briefly explain their meaning.
Table of Contents
CDi (Common-rail diesel injection) refers to diesel engines with direct fuel injection. These engines are equipped with a Common-rail system. CDi engines are used by the car companies Mercedes and Chrysler.
CDTi (Common-rail diesel turbo injection) refers to supercharged diesel engines with direct fuel injection. These engines are equipped with the Common-rail system and are used by Opel.
CRD (Common rail diesel) refers to diesel engines with direct fuel injection. Engines with this designation are used by the American automobile manufacturers Chrysler, Dodge, and Jeep.
CRDi (Common rail diesel injection) refers to diesel engines with direct fuel injection. The only difference from CRD is that this designation is used by Korean car companies such as Hyundai or Kia, but also by Japanese Mitsubishi, for example.
DDiS (Direct Diesel injection System) refers to a turbocharged diesel engine with the Common rail system of the Suzuki brand.
DTI (Direct Turbo Injection) refers to a turbocharged diesel engine with direct injection.
HDi (High-pressure direct injection) denotes an engine with high-pressure direct injection. These engines can be equipped with the OverBoost function (it increases power for a short time after pressing the pedal).
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JTD (Jet Turbo Diesel) refers to a turbocharged diesel engine with a Common rail system used by Fiat, Alfa Romeo, and Lancia. The first generation of common-rail diesel engines from Fiat under the designation JTD was also known under the initials uniJet Turbo Diesel.
JTDM, in other words, Jet Turbo Diesel Modified (Multijet), is a designation for engines with Common-rail technology and, thus, direct fuel injection.
Related article - Common Rail: How does it work, and what are its advantages?
Fiat was the first to come up with this system in 1997 with Alfa Romeo engines, followed by Mercedes-Benz. Fiat, Alfa Romeo, Lancia, Chrysler, Jeep, and Maserati widely use Multijet.
SDI (Suction diesel injection) refers to diesel engines with atmospheric filling and direct fuel injection produced by Volkswagen Group. Since these engines are not turbocharged, they provide less power compared to turbocharged engines of the same displacement.
SDI engines were produced as in-line four-cylinder or five-cylinder engines. Because they are structurally simpler than turbocharged engines, they are also more reliable, while consumption remains unchanged.
TDI (Turbocharged direct injection) refers to turbocharged diesel engines with direct injection produced by Volkswagen Group. In many countries, the abbreviation TDI is registered as a trademark of the Volkswagen Group, and these engines are widespread primarily in Europe.
TDI-PD (TDI – Pumpe Düse) refers to a turbocharged diesel engine with direct injection with a pump-nozzle unit.
TDDi (Turbo diesel direct injection) refers to diesel engines with direct fuel injection. Ford uses this designation. The newer generation of diesel engines (TDCi) has a more refined and less noisy operation compared to TDDi.
TDCi (Turbo diesel common-rail injection) refers to diesel engines with direct fuel injection with the Common-rail system. These engines are the newer generation of TDDi engines used by Ford.
We believe that after this article, the designations of diesel engines will no longer cause you any problems. However, if you did not find some engine designations in this list, do not hesitate to share a comment, and we will add it to the list.