1998–2005 GM 3800 Series II Harness + Tuned ECM Package — No Core Required

1998–2005 GM 3800 Series II Harness + Tuned ECM Package

Complete simplified wiring solution — tuned ECM included and no core required.

Built for 1998–2005 GM 3800 Series II engines, this LMMF package gives you the major wiring and computer components needed for a clean, dependable demolition derby, race, off-road, or engine-swap build. Choose the injector connector style that matches your engine, install the simplified harness, and get your build running without chasing down a usable ECM.

Tuned ECM included • No core required • Choose EV1 or Multec injectors • Kept in stock • Usually ships within 1–2 business days

Fits

• 1998–2005 GM 3800 Series II engines
• EV1 injector configurations
• Multec injector configurations
• Demolition derby, race, off-road, and simplified engine-swap builds

Choose Your Injector Style

• EV1 Injectors: Select this option if your engine uses EV1 injector connectors.
• Multec Injectors: Select this option if your engine uses Multec injector connectors.

Both EV1 and Multec configurations are kept in stock. If you are unsure which injector connection you have, contact LMMF before ordering.

What’s Included

• Professionally built simplified standalone 3800 Series II engine harness
• All-new wiring, new connectors, and quality components
• Tuned ECM matched to the package
• Your selected EV1 or Multec injector connector configuration

No Core Required

Your tuned ECM is included with the package. You do not need to send us an ECM core or return one after purchase.

Simple Hookup

This simplified setup requires only a basic two-wire power-and-ground hookup to get your engine running.

In Stock & Fast Shipping

Both EV1 and Multec versions are kept in stock and usually ship within 1–2 business days.

Before You Order

• Confirm that your engine is a 1998–2005 GM 3800 Series II.
• Select the injector style that matches your engine: EV1 or Multec.
• Contact LMMF before ordering if you are unsure about engine year, injector connection, or vehicle compatibility.
• For supercharged applications, shop the separate 3800 Supercharged Simplified Harness listing.
• Intended for off-road, race, engine-swap, and demolition derby use; not intended for emissions-controlled or street-driven vehicles.

Plug it in. Fire it up. Send it.