E-Z-GO ST 480 Fuel Pump Pressure

The gasoline E-Z-GO ST 480 utility vehicle uses a low-pressure carbureted fuel system. Check steady pump output and fuel delivery first, and only use a numeric pressure or volume target if the exact service manual provides one.

E-Z-GO Fuel Pressure Guide

ST 480 • Pressure + flow testing

Low-pressureFuel system

Flow firstPrimary test

Pulse-drivenPump type

No EFI targetImportant

ST 480 fuel pressure at a glance

Low-pressure carbureted system

Flow + pulse test first

Do not use an EFI PSI target. Verify inlet fuel, engine pulse/impulse and repeated pump outlet delivery.

Fuel at inletConfirm the tank, pickup and filter are supplying the pump.

Pulse/impulseInspect the engine pulse hose for leaks, blockage or collapse.

Outlet deliveryObserve repeated fuel output while cranking into an approved container.

Numeric specUse a pressure or volume number only if the exact service manual publishes one.

How to test the E-Z-GO ST 480 fuel pump

Confirm fresh fuel, a vented tank and an unrestricted filter before judging pump output.

Verify fuel reaches the pump inlet and inspect the pulse/impulse hose for splits, looseness, collapse or blockage.

Route the pump outlet safely into an approved container and crank the engine briefly to check repeated fuel delivery.

Use the exact service manual if a numeric pressure or volume specification is published for that model year.

Do not compare a carbureted diaphragm pump with a modern EFI pressure target such as 43.5 psi.

If inlet fuel and engine pulse are present but outlet delivery is weak, the pump or an immediate restriction becomes the likely fault.

How to interpret the ST 480 test result

Fuel reaches inlet, no outlet flow

Check pulse input; if pulse is good, suspect the pump.

Runs then dies

Tank vent, filter or suction-side restriction can slowly starve the carburetor.

Weak only under load

A marginal diaphragm pump or pulse leak may keep up at idle but not under demand.

New pump still weak

Recheck hose routing, pulse hose and upstream supply.

ST 480 fuel-system pressure details

Fuel system: Low-pressure carbureted / diaphragm pump.

Engine/system: Older gasoline / carbureted.

Pressure guidance: Use the exact low-pressure specification if published.

Applies to: Legacy gasoline versions.

Model-specific note

Legacy E-Z-GO gasoline models in this family commonly use a low-pressure diaphragm pump; do not apply modern 43.5 psi EFI figures to these carbureted systems.

E-Z-GO ST 480 fuel pressure FAQ

What fuel pressure should the E-Z-GO ST 480 have?

This is a low-pressure carbureted system on the gasoline versions covered by this page. Use the exact service manual if a numeric pressure or volume target is required.

How do I test E-Z-GO ST 480 fuel-pump flow?

Verify fuel reaches the inlet and that the pump receives an engine pulse, then observe repeated outlet delivery while cranking into an approved container.

Can I use a 43.5 psi test on an E-Z-GO ST 480?

No. 43.5 psi is an EFI-level specification used on specific modern systems, not a universal target for low-pressure carbureted diaphragm pumps.

Can the E-Z-GO ST 480 pump flow fuel but still be weak?

Yes. A marginal diaphragm pump may supply enough at idle but fail to keep the carburetor supplied under sustained load.

What causes weak E-Z-GO ST 480 fuel-pump output?

A weak diaphragm, poor engine pulse, leaking pulse hose, blocked filter, restricted pickup, collapsing suction hose or tank-vent problem can all reduce delivery.

Should I install a high-pressure electric pump on a carbureted E-Z-GO ST 480?

Not as a direct substitute. Use the pump and pressure or flow specification intended for the exact carbureted fuel system.

Verify with official documentation

Fuel-pump pressure, flow or volume targets and test procedures can vary by model year, engine and fuel-system generation. Before condemning a pump or ordering parts, confirm the specification in the official owner, operator, parts or service manual for your exact E-Z-GO ST 480. For current documentation, visit the official manufacturer website.