fuel pump prime when car is off. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Javi802 · 01-15-2015, 07:08 PM

Have any of you ever had this happen?

Sometimes, when ever i shut my car off and take the key out of the ignition, it sounds as if my fuel pump will prime...

And just last night when i was putting my rear shocks in, out of nowhere i hear what sounds to me like the fuel pump, priming. Keys weren't in the ignition. Only ever started recently..

Is this common on a faulty fuel pump?

kojiki88 · 01-15-2015, 08:25 PM

Same thing has happened to me. I have a Walbro 255 and a few months ago it did that so I changed my fuel pump out thinking it was that(4-5 years old). Put in the new one and everything seemed fined until it did it again, doesn't do it all the time and the car drives fine on and off boost so I stopped worrying about it.

Ilya · 01-15-2015, 09:23 PM

Happens to me too. I can't decide though whether it is the pump or the auto antenna. Ask me how much I care

pacotaco345 · 01-15-2015, 10:19 PM

fuel pump continues running for 5 seconds after your car is shut off

Javi802 · 01-16-2015, 07:25 AM

so do you know why it would randomly run, out of nowhere?

My car had been off for a few hours and i was underneath it doing some stuff and all of a sudden i hear the fuel pump.

Ilya · 01-16-2015, 07:34 AM

You are not the only one this happens to.

Javi802 · 01-16-2015, 07:41 AM

Lol alright. I just thought it was weird. Ive had the car for 3 years and its never happened before. 2 years with a ka in it and going on one year with the sr

Ilya · 01-16-2015, 07:55 AM

Yeah man. Mine just randomly started doing it and does it randomly. I'm still scratching my head why it would it at random times. I think mine is also ambient temperature dependent.
I've had crazy theories like air particles charging one of two capacitive plates aka body panels and then them discharging or, since my car is a vert, static charge building on the fabric and being released when I close the circuit somehow. Who knows

japslapsilvia · 01-16-2015, 01:01 PM

Quote:

Originally Posted by pacotaco345

fuel pump continues running for 5 seconds after your car is shut off

no it doesnt, well it shouldnt, the process is as follows, KOEO=fuel pump prime for ~5 seconds, without a crank,camangle sensor detected by the ECU fuel pump shuts off via the ECU. SO if your pump continues to run longer then 5 seconds with NO crank/camangle sensor, OR runs when you key off, then either the ECU has a fault, the fuel pump relay is sticking, OR there is a wiring issue. This is all based on the assumption that the wiring in the car is stock (unmodified)

Javi802 · 01-16-2015, 06:18 PM

Well the engine harness is a wiring specialties. Everything else has been left alone.

A new, bigger fuel pump was wired in when i first did the swap

01-15-2015, 07:08 PM	#1
Javi802 Zilvia Junkie Join Date: Jul 2012 Location: Oklahoma Age: 33 Posts: 472 Trader Rating: (10) Feedback Score: 10 reviews	fuel pump prime when car is off. Have any of you ever had this happen? Sometimes, when ever i shut my car off and take the key out of the ignition, it sounds as if my fuel pump will prime... And just last night when i was putting my rear shocks in, out of nowhere i hear what sounds to me like the fuel pump, priming. Keys weren't in the ignition. Only ever started recently.. Is this common on a faulty fuel pump?

01-15-2015, 08:25 PM	#2
kojiki88 Zilvia Member Join Date: May 2009 Location: New Mexico Age: 37 Posts: 245 Trader Rating: (4) Feedback Score: 4 reviews	Same thing has happened to me. I have a Walbro 255 and a few months ago it did that so I changed my fuel pump out thinking it was that(4-5 years old). Put in the new one and everything seemed fined until it did it again, doesn't do it all the time and the car drives fine on and off boost so I stopped worrying about it. __________________

01-15-2015, 10:19 PM	#4
pacotaco345 Zilvia FREAK! Join Date: Jan 2010 Location: SoCal/Ft Worth TX Age: 31 Posts: 1,563 Trader Rating: (5) Feedback Score: 5 reviews	fuel pump continues running for 5 seconds after your car is shut off __________________

01-15-2015, 09:23 PM	#3
Ilya Zilvia Addict Join Date: Jan 2008 Location: San Diego Age: 35 Posts: 712 Trader Rating: (2) Feedback Score: 2 reviews	Happens to me too. I can't decide though whether it is the pump or the auto antenna. Ask me how much I care

01-16-2015, 07:25 AM	#5
Javi802 Zilvia Junkie Join Date: Jul 2012 Location: Oklahoma Age: 33 Posts: 472 Trader Rating: (10) Feedback Score: 10 reviews	so do you know why it would randomly run, out of nowhere? My car had been off for a few hours and i was underneath it doing some stuff and all of a sudden i hear the fuel pump.

01-16-2015, 07:34 AM	#6
Ilya Zilvia Addict Join Date: Jan 2008 Location: San Diego Age: 35 Posts: 712 Trader Rating: (2) Feedback Score: 2 reviews	You are not the only one this happens to.

01-16-2015, 07:41 AM	#7
Javi802 Zilvia Junkie Join Date: Jul 2012 Location: Oklahoma Age: 33 Posts: 472 Trader Rating: (10) Feedback Score: 10 reviews	Lol alright. I just thought it was weird. Ive had the car for 3 years and its never happened before. 2 years with a ka in it and going on one year with the sr

01-16-2015, 07:55 AM	#8
Ilya Zilvia Addict Join Date: Jan 2008 Location: San Diego Age: 35 Posts: 712 Trader Rating: (2) Feedback Score: 2 reviews	Yeah man. Mine just randomly started doing it and does it randomly. I'm still scratching my head why it would it at random times. I think mine is also ambient temperature dependent. I've had crazy theories like air particles charging one of two capacitive plates aka body panels and then them discharging or, since my car is a vert, static charge building on the fabric and being released when I close the circuit somehow. Who knows

01-16-2015, 06:18 PM	#10
Javi802 Zilvia Junkie Join Date: Jul 2012 Location: Oklahoma Age: 33 Posts: 472 Trader Rating: (10) Feedback Score: 10 reviews	Well the engine harness is a wiring specialties. Everything else has been left alone. A new, bigger fuel pump was wired in when i first did the swap