2015 3.5 ecoboost cranks but slow to start

[redbone]

2015 expedition has recently having problems to start. Intermittently it will spin for maybe 5-10 seconds before it starts. Before it always started almost instantly. Plugs replaced 3 months ago. 165,000 miles. I was told it could be something that is letting fuel leak back from engine.

 

[jkayca]

Is the battery good?

 

[99WhiteC5Coupe]

2015 expedition has recently having problems to start. Intermittently it will spin for maybe 5-10 seconds before it starts. Before it always started almost instantly. Plugs replaced 3 months ago. 165,000 miles. I was told it could be something that is letting fuel leak back from engine.

Do you have a physical key or the intelligent fob (push-button start)?

After vehicle not started overnight, turn on the ignition but do not crank the engine. Wait several seconds, then crank.

If the engine starts quickly, it indicates a loss of fuel pump prime. When the ignition is turned to the “run” position - it causes the fuel pump to prime, prior to starting the engine.

If the fuel pump pressure regulator is bad, it can lose prime quickly - or slowly (overnight). It is part of the fuel pump module in the fuel tank.

 

[redbone]

Is the battery good?

Yes, new battery.

 

[redbone]

Do you have a physical key or the intelligent fob (push-button start)?

After vehicle not started overnight, turn on the ignition but do not crank the engine. Wait several seconds, then crank.

If the engine starts quickly, it indicates a loss of fuel pump prime. When the ignition is turned to the “run” position - it causes the fuel pump to prime, prior to starting the engine.

If the fuel pump pressure regulator is bad, it can lose prime quickly - or slowly (overnight). It is part of the fuel pump module in the fuel tank.

It has the push button start. It does seem to be worse after it sits over night. If it is the fuel pump pressure regulator, I assume I need to replace the fuel pump?

 

[99WhiteC5Coupe]

It has the push button start. It does seem to be worse after it sits over night. If it is the fuel pump pressure regulator, I assume I need to replace the fuel pump?

The fuel pump pressure regulator is part of the fuel pump module assembly.

One other check - once the vehicle starts and runs, shut off the vehicle. Then quickly try to restart it.

If the engine quickly starts without excessive cranking, that is a sign that the fuel pressure is good - but is bleeding off overnight (or for an extended shut-down period).

 

[redbone]

Yes it is slow to start after over night sitting. Once started it usually starts as normal. So I assume the fuel pump needs to be replaced?