Common Rail diesel fuel injection system: features, advantages & disadvantages ➤ AUTODOC CLUB

Common Rail is a fuel supply system used in modern diesel cars. Its main feature is the use of a fuel rail common to all fuel injectors which serves as an accumulator where fuel is stored under high pressure (up to 300 mPa). Fuel is fed into the rail by a high-pressure pump. From there it is supplied to the injectors and is injected directly into the engine cylinders. The injection timing, fuel metering, and number of injections per cycle are controlled by the ECU.

The Common Rail system has been installed on passenger cars since 1997. Nowadays, diesel engines of most passenger and commercial vehicles are equipped with it.

Engines equipped with the Common Rail system

Car make	Engine brand name	Engine models
Nissan, Dacia, Renault	dCi	K9K, R9M, F9Q, R9N, M9R, G9T, G9U, M9T, P9X, V9X
Mercedes-Benz	CDI	OM646, OM611, OM651, OM647, OM612, OM648, OM668, OM628, OM629
Mercedes-Benz	d	OM654, OM656
Opel, Vauxhall	CRI, CRI BiTurbo	X20DTL, Y20DTH, Z17DTL, Z17DTH, Z13DTH, Z19DTH
	CDTi	Z17DTH, A17DT, A13DTE, A17DTJ, Z17DTJ, G9U 630, A17DTR, A20DTH, Z13DTJ, Z13DTH, Z19DTH
	BiTurbo CDTI	A20DTR, B20DTR
Hyundai, KIA	CRDi	J3, D3FA, D4EB, D4CB, D4FC, D4FA, D4FB, D4FD, D4EA, D4HB, D6EA, G6EN, D3EA
Land Rover	ED4	204DTD
	TD4	224DT, DW12BTED4, 204D3, M47
	TDV8	448DT, 368DT
	TD6	276DT
	TDV6	306DT
	SDV6	30DDTX
	SDV8	448DT
	SD4	224DT
Citroën, Peugeot, DS, Volvo	HDI, HDi	DV4TD, DV4TED4, DV6TED4, DV6ATED4, DV6ETED, DW10TD
Citroën, Peugeot, DS, Volvo	BlueHDi, e-HDi	RHE (DW10CTED4), BHY (DV6FD), BHX (DV6FC), DV6FCTED, DW10FCTED4, DW10FC, DW10FDTED4, DV6FETED, DV6FE, DV5TED4
Fiat, Alfa Romeo, Lancia	JTD	182 B4.000, 188 A2.000, 185 A6.000, 839 A5.000, 186 A6.000, 182 B4.000, 182 B9.000, AR 34202, AR 32501, 937 A2.000
	JTDm	955 A4.000, 955 A3.000, 198 A2.000, 939 A7.000, 937 A6.000
	MultiJet	188 A8.000, 188 A9.000, 198 A3.000, 199 B1.000, 263 A1.000
Audi, Škoda, Volkswagen, Seat	TDI	CVMD, CAAC, DCXA, DBGC, DFGA, CLJA, CBAB,CAYC, BKS, BMK, CASA, CJMA, CRCA, CDUD, CKDA, DCZA
Audi, Škoda, Volkswagen, Seat	BiTDi	CDCA, CNEA, CSHA
Isuzu	DDi iTEQ	4JJ1
Chevrolet, Daewoo	VCDi	Z20S, Z20DMH, LLW, Z20S1, Z20D1, Z22D1
Honda	i-DTEC	N16A, N16A2, N22B1, N16A3, N22B3, N22B4
	i-CTDi	N22A1, N22A3
	CTDI	N22A2
Mazda	MZR-CD	RF7J, R2AA, RF5C, RF7J, Y601, Y642
	Skyactiv-D	S5-DPTS, S8-DPTS, SH-VPTS
	D	SHY1
	CiTD	RF5C
	DI Turbo	Y601
Mitsubishi	DI-D	4N13, 4N14, 4N15
SsangYong	XDi	D20DT, D27DT
	eXDI	D20DTF
	XVT	D27DTP
Volvo	Drive-E	D4204T8, D4204T14, D4204T23, D 4162 T
	D2	D5204T7, D4162T
	D3	D5204T5
	D4	D4204T5, D5204T
	D5	D5244T, D5244T5, D5244T15, D 5244 T9
Chrysler, Jeep	CRD	ENC, ENJ, ENS, ENR, EXF, EXA, ENE, ENF, EXL
BMW, MINI	d	N47 D20 C, N57 D30 A, N57 D30 B, B37 C15 A
BMW, MINI	SD, D	N47C20A
Ford	TDCi	F6JB, HHJC, UGJC, XVJA, XVJC, T1WB, QYBA, KHBA, T8CC, T1GA
Ford	Duratorq-TDCi	DV4TD, F6JA, F6JB, DV4TED4
Saab	TiD	Z19DT, Z19DTH, D223L
Saab	TTiD	A19DTR, Z19DTR, A 20 DTR
Toyota	D-4D	1ND-TV, 1WW, 1AD-FTV, 2KD-FTV
Toyota	D-CAT	2AD-FHV
Porsche	Diesel	M05.9E, M05.9D, MCU.DB, MCN.RB, MCR.CA, MCR.C, MCU.DC
Infinity	d	V9X, OM651
Subaru	D	EE20Z

Main components of the Common Rail system

Item No.	Name	Function
1	Low pressure fuel pump	Located in the fuel tank. Supplies fuel to the high-pressure pump.
2	Fuel filter	Removes dirt and various impurities from fuel and prevents the pump and injectors from wear.
3	High-pressure fuel pump	Feeds fuel under pressure into the fuel rail.
4	Fuel metering valve	Adjusts the amount of fuel fed to the high-pressure fuel pump.
5	Fuel pressure sensor	Measures the pressure in the fuel rail and sends a corresponding signal to the ECU.
6	Fuel rail	Contains fuel under high pressure.
7	Fuel pressure control valve	Relieves excess pressure in the fuel rail. This valve returns excess fuel back to the fuel tank. It is controlled by the ECU.
8	Injectors	Meter and spray fuel into the combustion chambers.

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0 261 500 01A BOSCH Injector

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A2C59513556 VDO Injector Nozzle

250,00 £

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0 280 158 164 BOSCH Injector

61,44 £

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0 280 158 124 BOSCH Injector

25,23 £

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A2C9626040080 VDO Injector Nozzle

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0 280 156 045 BOSCH Injector

37,36 £

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0 280 155 968 BOSCH Injector

46,56 £

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0 986 435 360 BOSCH Injector Nozzle

150,17 £

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0 261 500 494 BOSCH Injector

76,49 £

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Advantages and disadvantages of Common Rail engines

Advantages	Disadvantages
? Fuel efficiency	? Highly sensitive to fuel quality
? Eco-friendliness	? Injectors are sensitive to impurities
? Quiet operation	? Expensive and complicated repair
? High torque	? Fuel filters need to be replaced more frequently
? High power output

Den

a smiley technician with plenty of experience starring in AUTODOC's video tutorials; Never seen without his goggles; races his BMW X5 E53; dreams about receiving a Gold Play Button for getting 1,000,000 subscribers on YouTube.