Every injector swap question eventually becomes a connector question. This visual guide identifies the six connector families we see daily on the bench: Bosch EV1, USCAR, Denso 2 pin, Toyota side feed, Sumitomo, and Multec 2, with the retention style and keyway details that separate them. Compiled by the injector cleaning department at Boost Lab, Inc.
Match the housing shape and the retention method. The retention method is the most reliable tell: wire clips, molded latches, and rail keyways do not lie, while housing size can deceive between photos and real parts.
The old standard. Wide rectangular housing with two round pin cavities, retained by a separate steel wire clip that spans across the body and seats into grooves on the housing sides. If retention is a piece of sprung wire you can pop out, it is EV1.
The modern standard. Compact, nearly square housing with a molded press-down latch finger on top of the plug. Squeeze the tab to release. Found on LS2 and later GM, 2003-04 Cobra, and nearly all current aftermarket EV6 and EV14 injectors including Injector Dynamics and Fuel Injector Clinic.
The Nippon Denso 2 pin plug used across Toyota and Mazda top feed injectors from the late 1980s onward, including 7M-GTE, Gen 2 3S-GTE, and FC RX-7 applications. Squarish rounded housing with a side retainer clip rather than a top latch; the side clip is the family giveaway.
The grey Toyota 2 pin plugs on side feed injectors look nearly identical between families but are keyed differently: F1 on the JDM 440 cc and 1JZ injectors, F2 on the USDM 550 cc and Gen 3 3S-GTE units. The keyway position, not the housing size, is what to check before ordering pigtails.
Squarish housing with a center top latch, common on Honda B, D, and H series engines of the OBD1 era and some Mitsubishi applications. Frequently confused with USCAR at a glance; the latch geometry and cavity spacing differ, so OBD1 to OBD2 adapters exist for exactly this pair.
The compact Mini Delphi connector on GM Vortec truck injectors from 1999 through the mid 2000s, with a rounded oblong housing and top latch, paired with the short Multec injector body. If you are swapping LS3 style injectors into a truck rail, this is the connector you are adapting away from.
| Connector | Also Known As | Retention | Common Applications |
|---|---|---|---|
| Bosch EV1 | Jetronic, Minitimer | Steel wire spring clip | Fox and SN95 Mustang, Lightning, LS1, TPI, BMW M50 to S54, VW and Audi, most 1980s-90s EFI |
| USCAR | EV6 connector | Molded plastic latch | LS2 and later GM, 2003-04 Cobra, 2005+ Mustang, modern EV6 and EV14 aftermarket injectors |
| Denso / ND 2 pin | Nippon Denso | Side retainer clip, squarish housing | Toyota top feed, Mazda top feed, many Japanese applications |
| Toyota side feed F1 | JDM side feed | Keyed grey 2 pin, top latch | JDM 2JZ-GTE 440 cc, 1JZ-GTE |
| Toyota side feed F2 | USDM side feed | Keyed grey 2 pin, top latch | USDM 2JZ-GTE 550 cc, Gen 3 3S-GTE |
| Sumitomo | Honda OBD1 style | Center top latch | Honda B, D, H series, some Mitsubishi |
| Multec 2 | Mini Delphi | Top latch, rounded oblong housing | GM Vortec trucks 1999 to mid 2000s |
| Connector family tells you the plug, not the injector. Body style (EV1, EV6, EV14, side feed), o-ring sizes, and impedance are separate axes; Ford in particular mixed EV6 bodies with old Jetronic connectors for years. | |||
Look at the retention method. EV1 (Jetronic) uses a separate steel wire spring clip over a wide rectangular housing. EV6 style connectors use the compact USCAR housing with a molded plastic latch built into the plug. If you need a tool or fingernail to pop a wire clip, it is EV1; if you squeeze a plastic tab, it is USCAR.
Good quality adapters are fine for street and most performance use, and they avoid cutting a factory harness. For high vibration or high amperage low impedance applications, hard wiring new pigtails is the more durable choice. Either way, identify the connector correctly first; that is the step this page exists for.
Most current ID and FIC injectors are EV14 based units with USCAR connectors, and both brands offer or include adapters for common factory harnesses. As an authorized dealer for both, we can confirm the exact connector and adapter situation for any part number before you order.
Yes. Every set that comes across the bench is identified by body style, connector family, feed type, and impedance, and that identification is documented with your flow report. If you are planning an upgrade, that report tells you exactly which adapters or pigtails the swap needs.
Injector Lookup Database/Toyota Injector Reference/Mazda Rotary Injector Reference/Ford Injector Reference/Chevy and GM Injector Reference/BMW Injector Reference/Marine and Outboard Injector Reference/Fuel Injector Servicing