Motor Swap Chevy Truck

Recent motor swap, wont turn over, headlights come on when key is on accesory

Wiring problem?

Stock Harness.

ONLY wires touched were for throttle body and fuel ingection.

The first thing to check for after a motor swap and electrical problems arise is if all the grounds are reconnected. Such as from the engine to the firewall, engine to frame, and negative battery terminal to engine.

Tester

Try bypassing the ignition system and jump wire directly from the battery to the starter and see if the starter engages. If so it’s wiring…if not it’s probably the starter.

After 1981, engine swapping became an exercise in futility…Unless you are an electronics engineer, computer expert, hacker-spoofer it’s nothing but heartbreak and sorrow and boat-loads of money spent…