> When installing a new fuel pump on a fuel injected vehicle does the new fuel pump need to be primed?

When installing a new fuel pump on a fuel injected vehicle does the new fuel pump need to be primed?

Posted at: 2015-01-07 
Yes in a way...the fuel system lines probably have an air pocket in them which needs to be purged out in order for the fuel to reach the engine fuel rail. There is one fuel line from the tank/pump that feeds fuel to the engine fuel rail and a second return fuel line from the rail back to the tank to bleed off any excess fuel or pressure.

The usual procedure after installing a pump or fuel filter is to turn the ignition key to the Run or On position...not Start... and you should hear the fuel pump run for a few seconds. Turn the key back off and then back to Run/On again...not Start....and wait for a few seconds/pump to stop...do this several times so that the air is purged out of the fuel lines....then try starting as usual.

If you still have no fuel at the rail, add more fuel to the tank as the pickup tube in the tank may be sucking in air if the fuel levels are low which can burn out the pump...in tank pumps need flow of fuel to cool them. Might be a good idea to add more fuel anyway just to be safe.

You said there is no fuel getting to the fuel rail. That means you have checked the pressure at the Schrader valve or at least opened the valve and no fuel has come out right? If you haven't done that and there is no fuel then the instillation was not done right. Did you have to butt connect wires for the new pump? Double check the wires to make sure it is correct. The pump can run both ways and if your wrong it could run the pump but pump no fuel. If you have pressure at the Schrader valve look for spark as the reason it is not starting.

No-one has told you that you MAY well have a 'low-pressure lift-pump' which lives INSIDE your tank, and a 'high-pressure line-pump' which lives outside it, and looks like a Coke-can. In front of it will be a fuel-filter of smaller size. Have you changed this? Under £10. Also check all the hoses for splits, some can be incredibly small, like pinholes and hard to spot. Change all the rubber fuel lines for new ones, and use new petrol-pipe clips. You may well have gunge in your fuel lines, which is inhibiting fuel-flow.

No, you do not have to prime it after it is replaced. Saying that, you need to find out for sure if the pump is good or not. First put 5 gallons more gas in the tank and replace the fuel filter. See if it will start. If not you need to run a fuel pressure test to see if the pump is actually pumping fuel. It may be running but not actually pumping fuel. If the pump is defective replace it. You may need to use starter fluid to get the engine started as there will be no fuel in the line after replacing the filter. Most of the time if you have a good strong battery it will eventually start once the fuel reaches the engine.

The fuel pump does not need to be primed or bled. I hate to say it but it sounds like you've hooked up something backwards if you can hear the pump running and there is at least a gallon of gas in the tank.

No it does not it is submerged I the fuel tank when you turn on the ignition switch the fuel will start pumping

you still dont have enough gas in it either put 5 gallons minimum