This is the Bosch 0432133773, a new nozzle and holder assembly for the Cummins 4B and 4BT 3.9L four-cylinder engine. It replaces Cummins 3964919 and 4089468, and the injector body carries the ID 4919. It opens at 260 to 274 bar. It is a Bosch-made part, sold each, and the engine takes four.

Hard starting, white or black smoke, a rough idle, fuel knock and fuel in the oil are the usual signs of worn nozzles on these engines. Mechanical injectors wear as a set, so most shops test or replace all of them at once. A weak lift pump, air in the supply line or a worn injection pump cause the same complaints, so rule those out first. The 3.9L used several injectors over the years. They look alike and carry different numbers, so match the Cummins number or the body ID on your old injector.

Specifications

Fits / Applications

• Cummins 4B and 4BT 3.9L four-cylinder engines that call for injector 3964919 or 4089468
• Old injector stamped with body ID 4919
• Four injectors per engine

Fit a new sealing washer under each injector and make sure the old one is out of the bore. Flush the lines before you connect them, change the fuel filter and bleed the system. Torque the hold-down to the engine manual, not by feel.

Part Numbers & Cross Reference

Bosch 0432133773  ·  Cummins 3964919  ·  Cummins 4089468

Cross-reference numbers can change with engine serial, build year and emissions tier, so treat this list as a starting point. Send us your engine serial number and we will confirm the exact match against your build before anything ships. That check is free and takes a few minutes.

Frequently Asked Questions

What numbers does the Bosch 0432133773 replace?

Cummins 3964919 and 4089468. The body ID stamped on the injector is 4919.

Will it fit any Cummins 4BT 3.9L?

No. It is for the 3.9L builds that call for Cummins 3964919 or 4089468. Other 3.9L engines are listed with the 0432131694 (Cummins 3932123), the 0432131698 (Cummins 3930573) or the 0432133861 (Cummins 3926819). Call 530-668-0818 with your engine serial number.

What is the opening pressure?

260 to 274 bar. The 0432131694 and 0432131698 are set lower, at 240 to 254 bar, so check which number your engine calls for.

Is it new, and do I send my old injector back?

It is a new Bosch injector, not a rebuild. It is sold outright, so there is no core to return.

Related Parts

• Cummins 6BT & 6BTAA 5.9L Mechanical Fuel Injector (3939696, 4089270) | Bosch 0432133787 New
• Cummins 4BT 3.9L & 6BT 5.9L Mechanical Fuel Injector (3926819, 3802547) | Bosch 0432133861 New
• Cummins 4BT 3.9L & 6BT 5.9L Mechanical Fuel Injector (3930131, 3802748) | Bosch 0432131743 New
• Cummins 4BT 3.9L, Case, Kobelco VE4 Injection Pump 0460424081 | Bosch Authorized Remanufactured by VFI
• Mechanical Diesel Injector Testing & Rebuild Service

Why Buy From Valley Fuel Injection

We are a diesel fuel-injection and turbocharger shop in Woodland, CA, rebuilding pumps, injectors and turbos on our own benches since 1993, not a drop-ship storefront. When you call, you talk to the people who test these units. We verify fitment against your engine serial, VIN or build date before anything ships, so the right part arrives the first time.