Regeneration of Solaris Urbino injectors with Cummins and VDL Citea (DAF) engines

Solaris Urbino with Cummins engine and VDL Citea – two popular buses, two different injection systems

Solaris Urbino is one of the most common city buses in Poland. In addition to the version with Iveco Cursor engines, the manufacturer offered and still offers versions with Cummins ISB6.7 and Cummins ISL9 engines - valued for their reliability and ease of servicing. In turn, VDL Citea buses - a Dutch manufacturer, widely used by Polish and European transport companies - use DAF FR103 and FR106 engines with the Delphi and Bosch Common Rail system.

Both injection systems - Cummins XPI/CR with Denso and Delphi injectors, and DAF FR with Bosch injectors - require specialized service on a test bench. A-Core Diesel The service has software and calibration standards for both types, confirming each regeneration with a pre/post test report.

Injector catalog numbers – Cummins ISB/ISL and DAF FR (VDL)

Solaris Urbino with Cummins engines – Denso and Delphi injectors

Bus model	Engine	Injector type	Part number	Euro
Solaris Urbino 12 Cummins (E4)	ISB6.7 250B Euro 4	Denso DCRI105800	0 445 120 212 / 4 945 029	Euro 4
Solaris Urbino 12 Cummins (E5)	ISB6.7 280B Euro 5	Bosch CRI2-16	0 445 120 238 / 0 445 120 239	Euro 5
Solaris Urbino 18 Cummins (E5)	ISL9 340B Euro 5	Bosch CRI2-18	0 445 120 265 / 0 445 120 266	Euro 5
Solaris Urbino 12 Cummins (E6)	ISB6.7 Euro 6	Bosch CRI3-20	0 445 126 055 / 0 445 126 056	Euro 6
Solaris Urbino 18 Cummins (E6)	ISL9 380B Euro 6	Bosch CRI3-20	0 445 126 058 / 0 445 126 059	Euro 6

VDL Citea with DAF FR engines – Delphi and Bosch injectors

VDL model	Engine	Injector type	Part number	Euro
VDL Citea LLE-99 / SLE-120 (E4)	DAF FR103 S1 Euro 4	Delphi EJBR04201D	EJBR04201D / 1 367 030 080	Euro 4
VDL Citea LLE-115 / SLE-130 (E5)	DAF FR103 S2 Euro 5	Delphi EJBR04201D	EJBR04201D / EJBR05301D	Euro 5
VDL Citea SLFA-187 / LFA-122 (E6)	DAF FR106 S3 Euro 6	Bosch CRI3-20	0 445 126 020 / 0 445 126 021	Euro 6
VDL Citea SLE-135 (E6)	DAF FR106 S3 Euro 6	Bosch CRI3-20	0 445 126 022 / 0 445 126 023	Euro 6

Symptoms of injector damage - Cummins ISB/ISL and DAF FR

Characteristic symptoms of a worn injection system

• Uneven engine operation at idle speed - vibrations visible on the tachometer and felt in the driver's cabin
• Black or bluish smoke – when accelerating or starting from a stop
• Increase in fuel consumption – monitored by telematics systems of ZTM, MPK and private operators
• Error codes P0200–P0207 in Cummins INSITE or VDL DiagManager diagnostics
• Difficult cold start – especially below -5°C in buses operated at night
• Excessive back-leak – detectable by the return beaker test; Cummins standard: less than 2 ml/30 s
• Engine clatter – metallic sound from the head, characteristic of a damaged solenoid valve

Error Codes – Cummins INSITE (ISB6.7 / ISL9)

SPN/FMI Code	Description	Applies to
SPN 651–656 FMI 5/6/7	Injector coil cyl. 1–6 – missing / short circuit / break	ISB6.7 / ISL9
SPN 157 FMI 1	CR bus pressure too low below starting threshold	ISB6.7 / ISL9
SPN 094 FMI 1/3	Fuel pressure outside the allowable range	all
SPN 2791 FMI 2	Injection dose correction - cyl. 1-6 outside the norm	ISL9 E6
SPN 1239 FMI 2	System leakage - excessive back-leak	all
Fault 559	Rail pressure sensor – deviation from the norm	ISB6.7 E4/E5

Error codes – VDL Citea / DAF FR (VDL DiagManager)

Code	Description	Applies to
P0201–P0206	Cylinder injector circuit. 1–6 – break	DAF FR103 / FR106
P0261–P0272	Low / high coil signal - cyl. 1–6	all
P0087	Rail pressure too low	all
U1001	No communication between ECU and injector module	DAF FR106 E6

Regeneration of injectors – procedure for both types

Pre-test on the Bosch EPS 815 table

Each injector from a Solaris or VDL bus goes to the Bosch EPS 815 test bench with the current parameter database for Denso DCRI, Delphi EJBR and Bosch CRI2/CRI3. We record doses at start-up, idle and full load, back-leak and the response time of the solenoid valve. The pre-test documents the condition of the injector before regeneration.

Disassembly and inspection under clean conditions

Cummins injectors with Denso DCRI injectors require special attention when dismantling the control valve - manufacturing tolerances are narrower than in standard CRI2 Bosch. We check the needle clearance (Denso standard: below 1 μm), the condition of the nozzle seat and seals, the resistance of the solenoid valve coil and the condition of the inlet filters and fuel channels.

Replacement of components and calibration to 1 μm

We use original repair kits from Denso, Delphi (7135-573 / 7135-574 / 7135-652 for EJBR) and Bosch (F 00V C99 004–006 for CRI3). Calibration of spacer washers regulating the nozzle opening pressure is performed with an accuracy of 1 μm.

Post-test and final report

Each remanufactured injector undergoes a full final test. Acceptance only for results within a tolerance of ±2% from nominal values. The customer receives a printout of the report with the serial number, date and results of both tests (pre and post).

Supported bus models

• Solaris Urbino 8.9 / 10.5 / 12 / 15 / 18 with Cummins ISB6.7 and ISL9 engines, Euro 4–6
• Solaris Alpino 8.6 / 10.8 – Cummins ISBe 4.5 and ISBe 6.7, Euro 3–5
• VDL Citea LLE / SLE / SLFA / LFA – DAF FR103 and FR106, Euro 4–6
• VDL Berkhof Ambassador – DAF FR, Euro 3–5
• Ikarus 280 / 415 with Cummins ISBe engine – modernized versions

Shipping service and fleet management

For communication plants operating mixed Solaris + VDL fleets, we offer common service in one order - regeneration of various types of injectors in one shipment, one collective report. Delivery time: 3-5 business days. For fleets of over 20 vehicles – individually agreed conditions and a dedicated technician. Contact: +48 504 511 170, Mon–Fri 8:00–16:00.

FAQ

Are Denso injectors from Solaris Urbino Cummins ISB6.7 Euro 4 and Euro 5 the same?

No – Euro 4 uses Denso DCRI105800 (no. 0 445 120 212), Euro 5 – Bosch CRI2-16 (0 445 120 238). These are different generations with a different design of the control valve. Before ordering, we identify the type based on the engine number and year of production of the vehicle.

Does VDL Citea with DAF FR106 Euro 6 engine require reprogramming after regeneration?

Bosch CRI3-20 injectors in DAF FR106 Euro 6 may require updating the correction values in the ECU via VDL DiagManager or DAF DAVIE - we recommend that this procedure be performed by an authorized VDL or DAF service after installation.

Can I send injectors from several buses in one shipment?

Yes - please mark each injector separately (registration number or vehicle inventory number + cylinder number). We accept collective shipments from communication companies and fleet operators.

How often should the injectors be serviced in Solaris Urbino with Cummins?

In case of intensive urban use (200+ thousand km/year), we recommend the first diagnostics after 500,000-700,000 km or when the first symptoms appear. Regularly replacing Cummins Fleetguard fuel filters every 60,000 km significantly extends the life of the injectors.

Contact

A-Core Diesel Serwis, Knurów (Silesia)
Tel.: +48 504 511 170 – Mon–Fri 8:00–16:00
Free quote after initial diagnostics. Shipping service – all over Poland.