BMW E30 M30 Trackday Missle Fuel pump circuit upgrade.

Just a quick video to go over the wiiring upgrade to hopefully stop my e30 killing pumps. Pump number 5 is the charm! I ran 6mm twin core copper cable from the engine bay straight to the pump and added in my own relay and 30A auto reset circuit breaker to the existing ECU pump trigger circuit that piggybacks off the fuel injector power circuit (red/white) and the O2 sensor wire (green/violet) to get the signal. Its important that the relay gets its signal from the ECU so the pump circuit is disabled when the ECU turns off the injectors rather than being seperately switched so if the car crashes and the engine stalls your pump circuit stops too! It sure looks like a dogs breakfast but if you ever put an e34 wiring loom into an e30 you would understand!

Added 11 May 2026