Where is the part number on a fuel injector?

Typically, the part number is stamped or printed directly on the injector body—most often on the side near the electrical connector or near the nozzle base. It can vary by brand, so inspect the metal body, the plastic connector housing, and any labels or stickers on the part.

Where to look on injector bodies

Different injector designs place the part number in a few common spots. The following locations are the most frequently encountered across brands:

• Side of the metal injector body, usually near the electrical connector


• Near the base where the nozzle meets the body


• On the plastic connector housing or cap, sometimes as a label or printed code


• On the top of the injector body near the fuel inlet, in some Bosch/Denso designs

Because some units use labels rather than direct stamping, you may need to clean the surface and check both sides and ends of the injector to reveal markings.

Brand-specific clues and labeling

Bosch/Siemens style injectors

On many Bosch-style injectors, the part number is stamped or laser-etched into the metal body, often on the side near the top or close to the electrical connector. Some units also carry a separate label with the code.

Delphi/Siemens common-rail injectors

Delphi/Siemens units frequently have the part number stamped on the outer shell, typically along the side of the body near the nozzle or near the fuel inlet, sometimes under a protective sleeve.

Denso and related brands

Denso and similar brands commonly place the part number on the upper portion of the body near the electrical connection, or along the side; some models show a label on the connector.

How to verify and cross-reference the part number

Because injector part numbers are model- and engine-specific, follow these steps to confirm you have the right part:

• Compare the marking you find with the OEM part number in the vehicle service manual or dealership catalog


• Check the packaging or injector kit box for the OE or replacement part number and cross-reference with manufacturer catalogs


• Use your vehicle’s VIN, engine family, or injector family to search the manufacturer’s online catalog for the correct part


• When ordering, prefer OEM-grade injectors or reputable aftermarket equivalents that explicitly list compatibility for your engine

Verifying the exact match helps ensure correct spray pattern, connector type, and fuel-pressure compatibility.

What to do if the number is hard to read

If grime obscures the code, clean the injector with a mild solvent and recheck. Use a magnifying glass or smartphone camera to read tiny engravings. If unreadable, rely on the vehicle's OEM part numbers from manuals, service databases, or the injector kit packaging to identify the correct replacement.

Summary

In most cases, the part number on a fuel injector is embossed or printed on the injector body itself, most often along the side near the electrical connector or at the base near the nozzle. Brand-specific placements vary, and some units use labels instead of stamping. For accuracy, cross-reference any markings with OEM catalogs and packaging, and when in doubt, consult a professional mechanic or parts specialist.

Do injectors have serial numbers?

Many injectors will have the code stamped on the solenoid. Other injectors, like Delphi injectors, have a sticker on the body. Some Bosch common rail injectors have the trim code on the top of the plastic housing. You might find it on the injector coil.

Where is the injector code located?

Here's how to find the injector IMA/ISA code you need to enter in VCDS: 🔎 Where the code is located It's not the Bosch part number (0 445 110 …) or the VW part number (03L …). It's usually laser-etched on the injector body / solenoid housing, often on the side, not the top.

How to know what fuel injectors to get?

Choosing the right injectors for your engine

1. Determine engine specifications. Start by gathering all relevant engine specifications, including horsepower, BSFC, fuel type, and the number of cylinders.
2. Consider fuel system upgrades.
3. Consult with experts.
4. Test and tune.

How do I find my injector part number?

To find a fuel injector part number, locate the numbers or letters stamped or printed on the injector's body, solenoid, or a sticker on its side. For some diesel engines, you may need to look for a specific trim code, which is often found on the top of the solenoid. After identifying the number, you can search for the part number online or consult the vehicle's manual for specifics on its application and flow rate. 
You can watch this video to learn how to identify the part number on your fuel injector: 55sFiTech Fuel InjectionYouTube · Mar 22, 2023
Step-by-step guide

1. Locate the injector: Find the fuel injectors in your engine, which are usually located on the engine's intake manifold. 
2. Identify the markings: Look for a part number, trim code, or serial number printed or stamped on the injector. This is often found on: 
   • The solenoid (the top part of the injector). 
   • The body of the injector. 
   • A sticker on the injector's body (common on Delphi injectors). 
3. Note the code: Carefully read and write down the specific numbers and letters. For some diesel injectors, the last three digits on the top right of the solenoid may be the key identifier. 
4. Cross-reference: Search for the part number online, or use the vehicle's make, model, and engine code to find the correct injector. 
5. Check the ECM for trim codes: If you are replacing an injector in a modern diesel engine, use a scan tool to read the injector quantity adjustment (IQA) codes stored in the engine control module (ECM) to ensure you get the precise part for your engine. 

This video explains how diesel fuel injector trim codes work: 52sFlying WrenchesYouTube · Aug 18, 2023