The SDI engine is a design of naturally aspirated (NA) direct injection

diesel engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...

developed and produced by

Volkswagen Group Volkswagen AG (), known internationally as the Volkswagen Group, is a German multinational automotive manufacturer headquartered in Wolfsburg, Lower Saxony, Germany. The company designs, manufactures and distributes passenger and commercial ...

for use in cars and vans, along with marine engine (

Volkswagen Marine Volkswagen AG (), known internationally as the Volkswagen Group, is a German multinational automotive manufacturer headquartered in Wolfsburg, Lower Saxony, Germany. The company designs, manufactures and distributes passenger and commercial ...

) and

Volkswagen Industrial Motor Volkswagen (),English: , . abbreviated as VW (), is a German motor vehicle manufacturer headquartered in Wolfsburg, Lower Saxony, Germany. Founded in 1937 by the German Labour Front under the Nazi Party and revived into a global brand post-W ...

applications. The SDI brand name (derived from "Suction Diesel Injection" or "Suction Diesel Direct Injection", the latter a literal translation of the german: Saugdiesel-Direkteinspritzung) was adopted in order to differentiate between earlier and less efficient

indirect injection Indirect injection in an internal combustion engine is fuel injection where fuel is not directly injected into the combustion chamber. Gasoline engines equipped with indirect injection systems, wherein a fuel injector delivers the fuel at some p ...

engines, called SD or "Suction Diesel", which were also produced by Volkswagen Group. SDI engines are only produced in inline or straight

engine configuration The engine configuration describes the fundamental operating principles by which internal combustion engines are categorized. Piston engines are often categorized by their cylinder layout, valves and camshafts. Wankel engines are often categorize ...

s; and as they originate from a German manufacture, are designated as either R4 or R5, taken from the german: Reihenmotor. They are available in various displacements (from 1.7 to 2.5 litres), in

inline-four A straight-four engine (also called an inline-four) is a four-cylinder piston engine where cylinders are arranged in a line along a common crankshaft. The vast majority of automotive four-cylinder engines use a straight-four layout (with the e ...

(R4 or I4) and inline-five (R5 or I5), in various states of tune, depending on intended application. The SDI engine is generally utilised in applications where

reliability Reliability, reliable, or unreliable may refer to: Science, technology, and mathematics Computing * Data reliability (disambiguation), a property of some disk arrays in computer storage * High availability * Reliability (computer networking), a ...

and fuel economy are of primary concern. These engines lack any type of

forced induction In an internal combustion engine, forced induction is where turbocharging or supercharging is used to increase the density of the intake air. Engines without forced induction are classified as naturally aspirated. Operating principle Overvi ...

, hence the use of 'suction' in the title, and their power output is lower than a turbocharged engine of similar displacement. For example, the 2.0 SDI engine fitted to the

Volkswagen Golf Mk5 The Volkswagen Golf Mk5 (codenamed ''Typ 1K'') is a compact car/small family car manufactured and marketed by Volkswagen, as the fifth generation of the Golf in three- or five-door hatchback (August 2003–2008) and a five-door station wagon ...

has a peak power output of ; whereas the same engine in

Turbocharged Direct Injection TDI (Turbocharged Direct Injection) is Volkswagen Group's term for its current common rail direct injection turbodiesel engine range that have an intercooler in addition to the turbo compressor. TDI engines are used in motor vehicles sold by th ...

(TDI) form is rated at or , depending on specifications.

SDI engines and applications

}) electronic distributor

injection pump An Injection Pump is the device that pumps fuel into the cylinders of a diesel engine. Traditionally, the injection pump was driven indirectly from the crankshaft by gears, chains or a toothed belt (often the timing belt) that also drives the ca ...

, ,

Volkswagen Lupo The Volkswagen Lupo (''Typ'' 6X) is a city car that was produced by the German car manufacturer Volkswagen, from 1998 to 2005. It shares most of its aspects with the Volkswagen Group's SEAT Arosa, both derived from the Volkswagen Polo Mk3 platfor ...

SEAT Arosa The SEAT Arosa (''Typ'' 6H) is a city car that was manufactured by the Spanish automaker SEAT from 1997 to 2004. The model débuted in March 1997 at the Geneva Motor Show, while its facelifted version was presented in October 2000 at the Paris Mot ...

Volkswagen Polo The Volkswagen Polo is a supermini car ( B-segment) produced by the German car manufacturer Volkswagen since 1975. It is sold in Europe and other markets worldwide in hatchback, saloon, and estate variants throughout its production run. Histor ...

(some markets),

Volkswagen Caddy The Volkswagen Caddy is a panel van and leisure activity vehicle (M-segment) produced by the German automaker Volkswagen Group since 1980. It is sold in Europe and in other markets around the world. The Volkswagen Caddy was first introduced in Nor ...

''Typ'' 9K , -valign="top" , 1.9 SDI, , ASY, AEY, AGD, , , , @ 4,200, ,
@ 1,600-2,800, , Bosch VP37 (''VerteilerPumpe'') electronic distributor injection pump, ,

Volkswagen Polo Mk3 The Volkswagen Polo Mk3 (''Typ'' 6N/6KV) is the third generation of the Volkswagen Polo supermini car and was produced from 1994 until 2002, with a facelift at the end of 1999. It was available in hatchback, sedan and wagon body styles. Although t ...

, Volkswagen Polo Classic, Volkswagen Golf Mk3,

''Typ'' 9U/9K,

SEAT Inca The SEAT Inca (''Typ'' 9K) was a van and panel van produced by the Spanish manufacturer SEAT between 1996 and 2004. It was designed and assembled in Spain, based on the SEAT Ibiza Mark 2. It was first shown at the Barcelona Motor Show of 1995. ...

Škoda Octavia The Škoda Octavia is a small family car produced by the Czech car manufacturer Škoda Auto since the end of 1996. It shares its name with an earlier model produced between 1959 and 1971. Four generations of the modern-era Octavia model have ...

(Mk1),

Škoda Fabia The Škoda Fabia is a supermini car produced by Czech manufacturer Škoda Auto since 1999. It is the successor of the Škoda Felicia, which was discontinued in 2001. The Fabia was available in hatchback, estate (named Fabia Combi) and saloo ...

Volkswagen Bora The Volkswagen Bora is a small family car, the fourth generation of the Volkswagen Jetta, and the successor to the Volkswagen Vento. Production of the car began in July 1999. Carrying on the wind nomenclature from previous generations, the car wa ...

(some markets), Volkswagen Jetta King, Volkswagen Jetta Pioneer , -valign="top" , 1.9 SDI, , AGP, AQM, , , , @ 4,000, ,
@ 1,800, , Bosch VP37 (''VerteilerPumpe'') electronic distributor injection pump, ,

Volkswagen Golf Mk4 The Volkswagen Golf Mk4 (or VW ''Type 1J'') is a compact car, the fourth generation of the Volkswagen Golf and the successor to the Volkswagen Golf Mk3. Launched in October 1997 for the 1998 model year, it was the best selling car in Europe in 2 ...

''Typ'' 9U/9K,

SEAT Ibiza The SEAT Ibiza is a supermini car that has been manufactured by Spanish car manufacturer SEAT since 1984. It is SEAT's best-selling car. The Ibiza is named after the Spanish island of Ibiza and was the second SEAT model to be named after a Spa ...

, SEAT León Mk1 (1M),

(Mk1)

(some markets) , -valign="top" , , , BDJ, BST, , , , @ 4,200, ,
@ 2,200-2,400, , Bosch Pumpe Düse
technology, ,

''Typ'' 2K , -valign="top" , , , BDK, , , , @ 4,200, ,
@ 2,200-2,400, , Bosch Pumpe Düse
technology, ,

, -valign="top" , , , AGX, , , , , , , , Inline-five engine, Bosch VP37 (''VerteilerPumpe'') electronic distributor injection pump, ,

Volkswagen LT The Volkswagen Transporter LT is the largest light commercial panel van produced by Volkswagen (and subsequently Volkswagen Commercial Vehicles as of 1996) from 1975 to 2006, before being replaced by the Crafter. Two generations were produced ...

28 and LT35 vans (05/96-04/01) , - !colspan=7, '' marine engines'' , -valign="top" , 1.9 SDI
, , SDI 40–4,
SDI 50–4,
SDI 60-4, , , ,
@ 3,000 /
@ 3,600, ,
@ 2,000 /
@ 2,000, , Bosch VP37 (''VerteilerPumpe'') electronic distributor injection pump, , Small motor cruisers. Optional connection for

heater core A heater core is a radiator-like device used in heating the cabin of a vehicle. Hot coolant from the vehicle's engine is passed through a winding tube of the core, a heat exchanger between coolant and cabin air. Fins attached to the core tubes ser ...

or hot water preparation for use in

sailboats A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture. Types Although sailboat terminology ...

, -valign="top" ,
, , SDI 55–5,
SDI 75-5, , , ,
@ 3,600, ,
@ 2,250, , Inline-five engine, Bosch VP37 (''VerteilerPumpe'') electronic distributor injection pump, ,

Yachts A yacht is a sailing or power vessel used for pleasure, cruising, or racing. There is no standard definition, though the term generally applies to vessels with a cabin intended for overnight use. To be termed a , as opposed to a , such a pleasu ...

and motor cruisers , - !colspan=7, ''industrial engines (80/1269/EEC-rated)'' , -valign="top" , 1.9 SDI
, , 430/BXT, , , , , , , , Bosch VP37 (VerteilerPumpe) electronic distributor injection pump, ,

, -valign="top" , 1.9 SDI
, , 444, , , , @ 3,600, ,
@ 2,200, , Bosch VP37 (VerteilerPumpe) electronic distributor injection pump, ,

:Notes:

engines were originally rated according to Directive 80/1269/ EEC. However, some are now being rated to ISO 8178-4.

Lubricants

Like their related Volkswagen Group

diesel engines, Volkswagen AG requires that motor oil lubricants for SDI engines must conform to one of the officially approved standards VW505.00, 505.01, 506.00, 506.01, or 507.00. 'Generic' oil standards such as the

American Petroleum Institute The American Petroleum Institute (API) is the largest U.S. trade association for the oil and natural gas industry. It claims to represent nearly 600 corporations involved in production, refinement, distribution, and many other aspects of the ...

'API', or

European Automobile Manufacturers Association The European Automobile Manufacturers Association (french: Association des Constructeurs Européens d'Automobiles; abbreviated ACEA) is the main lobbying and standards group of the automobile industry in the European Union. In February 1991 it b ...

'ACEA' are not in themselves recognised or approved by VW, although such an oil may also conform to one of the specific VW standards. Many formulations of motor oils from most brands are now "VW Approved" to the above standards. However some unapproved 'off brands' print the VW number on the label, implying that they meet the said standard, but hide in small type the word "recommended". Only Volkswagen AG can grant the necessary approvals, following in-house testing. Volkswagen Germany (and Volkswagen of America) publish up-to-date lists of currently approved oils on their respective websites, along with the technical resource, erWin. All SDI-engined models with "LongLife Servicing", "Extended Service Intervals", "ESI", or "WIV", must be lubricated by official 'LongLife' lubricants, namely VW506.00 (for non-PD), VW506.01 (for PD), or VW507.00. According to VW 'generic' longlife lubricants, or those certified by other manufacturers such as General Motors, BMW or

Mercedes-Benz Mercedes-Benz (), commonly referred to as Mercedes and sometimes as Benz, is a German luxury and commercial vehicle automotive brand established in 1926. Mercedes-Benz AG (a Mercedes-Benz Group subsidiary established in 2019) is headquartere ...

should not be used.

SDI vs other VW Group diesel engines

The following table contains a selection of current and historical

compression-ignition SDI diesel engines for comparison of performance and operating characteristics with other naturally aspirated and forced induction engines of the same capacity:

References

External links

VolkswagenAG.com
– Volkswagen Group corporate website

{{Volkswagen Group brands Volkswagen Group diesel engines Diesel engines by model Fuel injection systems Marine diesel engines