BMW E31 850i / 850Ci / 850CSi Complete Fuel Pump Assembly — V12 M70 & S70 (Replaces OEM 16147159310)

A complete, brand-new fuel pump assembly for the V12 BMW E31 — the 850i and 850Ci on the M70 engine (1990–1994) and the 850CSi on the S70 (1992–1997). Developed over two years and precision injection-moulded to factory standards, it engineers out the failure points that leave these cars leaking fuel and running lean.

On the original, up to half of assemblies eventually crack at the moulding parting line below the injection mark, weeping fuel as the plastic heat-cycles over decades. The redesigned top cap is uniformly strong and crack-resistant. The factory’s brittle preformed plastic fuel lines — which degrade fast on modern E10 and ethanol-blended fuels — are replaced with high-pressure, fuel-resistant PTFE lines. That stops the pressure loss at the pump-motor connection that causes rough idling, low power on one or both banks, and lean running. A new top rubber seal is included.

Key specifications

Fits these vehicles