How to Read Bosch Diesel Part Numbers: A Complete Guide

A Bosch diesel part can carry four or five different numbers at once — the Bosch number, an aftermarket number, a nozzle code, the OE number from the engine maker. Knowing how to read them turns a confusing string of digits into a precise identification, and stops you ordering the wrong part.

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If you have ever stared at a fuel injector covered in numbers and wondered which one to actually order, you are not alone. Bosch uses a structured numbering system that, once you understand it, tells you the type of part, its product family, and even details like a nozzle’s spray angle. This guide breaks it down so you can identify any Bosch diesel component with confidence — and find the right replacement faster.

The anatomy of a Bosch part number

Most Bosch diesel part numbers are 10 digits long and are usually written in spaced groups, for example 0 445 120 187. The grouping is not decoration — it reflects the structure of the number.

The first digit (or first group) tells you the broad family the part belongs to:

• Numbers beginning 0 4… are original Bosch production parts (injectors, pumps, nozzles, and so on).
• Numbers beginning 0 9…, most commonly 0 986…, are Bosch aftermarket and Bosch eXchange (factory-remanufactured) reference numbers.
• Numbers beginning F0… (such as F00R, F00V, F00B) are used for modern common rail components — injector valve sets, control valves, and high-pressure pump assemblies.

So the same physical injector can legitimately wear both a 0 445 120 … original number and a 0 986 435 … aftermarket number. They are not different parts — they are two valid ways of referring to the same one.

You will find the number stamped or laser-etched on the component body, on a metal ID tag riveted to the housing, on a parts sticker, or moulded into the plastic.

The product families that matter most

Here is where the system becomes genuinely useful. The middle groups of the number identify the product family. These are the ranges you will meet most often on heavy-duty and industrial diesel engines:

Common rail injectors

• 0 445 110 xxx — CRI common rail injectors, typically for light and medium engines.
• 0 445 120 xxx — CRIN common rail injectors for commercial, heavy-duty and industrial engines.
• 0 445 124 xxx — newer-generation CRIN injectors (later high-pressure systems).

Unit pumps and unit injectors

• 0 414 7xx xxx — unit injector (UIS) and unit pump (UPS) systems, common on Mercedes-Benz, Volvo, Liebherr and Iveco engines.

High-pressure and mechanical pumps

• 0 445 020 xxx — CP-series common rail high-pressure pumps.
• 0 460 4xx xxx — VE/VR rotary distributor pumps (agricultural and lighter applications).
• 0 402 xxx xxx — PE inline injection pumps (heavy-duty and industrial).

Not sure how these pump types actually differ? Our guide to diesel injection pump types explains how each one works and where you’ll find it.

Nozzles

• 0 433 1xx xxx — injector nozzles, each also carrying a DLLA designation code (more on that below).

Electrics and components

• 0 001 3xx xxx — starter motors.
• 1 986 Axx xxx / 0 124 xxx xxx — alternators (aftermarket and OE numbering).
• 2 4xx xxx xxx — internal pump components: housings, camshafts, valves, springs and seals.

Recognising the family at a glance means you instantly know whether you are looking at an injector, a pump, a nozzle or a component — before you even cross-reference it.

Decoding a nozzle (DLLA) code

Injector nozzles carry their own designation alongside the 10-digit number, and it actually encodes physical characteristics. Take DLLA 145 P 2144:

• DLLA — the nozzle type designation (a multi-hole nozzle for direct injection).
• 145 — the spray cone angle in degrees. This is critical: a nozzle with the wrong spray angle will not atomise fuel correctly for your combustion chamber.
• P — the nozzle body/needle size series.
• 2144 — Bosch’s sequential design index, which ties the nozzle to a specific injector and application.

That same nozzle, DLLA145P2144, is also 0 433 172 144 in Bosch’s standard numbering — and it is the nozzle fitted inside injector 0 445 120 187. One component, several numbers, all pointing to the same physical part.

The cross-reference trap (and how to avoid it)

This is where buyers most often go wrong. A single injector might appear under all of these at once:

• a Bosch CRIN number — 0 445 120 187
• a Bosch aftermarket number — 0 986 435 573
• a nozzle code — DLLA145P2144 / 0 433 172 144
• and one or more OE numbers from the engine manufacturer (Cummins, MAN, Mercedes, etc.)

All of them are correct. The mistake is assuming two different-looking numbers must be two different parts, or ordering a nozzle code when you actually need the complete injector. The rule of thumb: identify what type of part you need first (whole injector, nozzle only, valve set, pump), then match the number within that family.

If you only have an OE number from your engine, that is fine too — it almost always cross-references back to a Bosch number, and a good supplier can do that lookup for you.

Where to find the number on the part

If the part is already in your hand:

• Injectors — etched on the body and on the solenoid valve area; the nozzle code is on the nozzle itself.
• Pumps — on a metal ID plate riveted or screwed to the pump housing.
• Starters and alternators — on a label or stamped tag on the casing.

Always work from the number on the part itself where possible, rather than the number in an old invoice, which may refer to a superseded version. And once you have identified the part, make sure it is genuine — our guide on how to spot a counterfeit Bosch injector walks through the checks.

Find your part by number

At CENTE, our entire catalogue is organised by Bosch and OEM numbers, so whichever number you are holding, you can match it directly. Browse by family:

• Diesel injectors and nozzles
• Fuel pumps — common rail, unit and distributor
• Pump components and repair parts
• Starter motors
• Alternators

Still not sure which number is the right one? That is exactly what we are here for.

Send us any Bosch or OE number and we will identify the correct part and confirm availability — get a quote within 24 hours →

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CENTE — Bosch diesel parts supplier, shipping across Europe.