Fuel pump is not engaging?

KAPOKIS72

MEMBER
2008 KIA SORENTO
3.3L
V6
2WD
AUTOMATIC
223,000 MILES

I have changed the purge valve. The crank shaft sensors I've checked the relay fuse. I've checked the regular fuses. And I have changed the fuel pump itself. But still when I turn the key on. It's not engaging and it's lagging when it starts. It first started lagging when I would get gas. Then it became every time I go to start it. It is lagging to start after I've done all this stuff to it.

Sunday, September 29th, 2024 AT 7:13 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Hi,

The PCM provides a ground path to complete the primary side of the pump relay. So, I have to ask if the fuel pump relay and the main relay have been checked? Not the fuses for them but in this case the relay itself. If not, switch them with a different relay having the same part number and see if that makes a difference.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Next, when the vehicle does start, do you ever notice any strong exhaust odors or dark smoke from the exhaust? Is the check engine light staying on after the engine is running? If so, have you scanned the computer for codes?

Let me know.

Joe

See pic below. Note: I highlighted the green wire with a black tracer. That is what runs to the PCM to provide a ground to the primary side of the relay.

Image (Click to make bigger)