Fuel pump woes - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Ninjabread · 03-28-2008, 07:33 PM

Just need some confirmation. Car used to start just fine before I put it away for winter.

I fiddled with the engine wiring harness, put it all back together and now it doesn't want to start. It cranks, but no fuel.

So I started checking around with a multimeter. I checked the fuel pump signal from ecu, and it gave me 12v, changed the fuse, even checked there, 12v as well. I jumped the 1-3 terminals on the relay to test that out, and no difference (both getting 12v).

Go to the back of the car, I unplug the fuel pump harness, test it and the two middle prongs (holes or whatever you want to call them... receptacles?) are getting 12v.

Does this mean my walbro is dead?

KiLLeR2001 · 03-29-2008, 12:11 AM

I'm assuming it doesn't prime at all, correct? Did you check all your ground wires?

If everything else checks out the pump is the only thing left. You didn't drive it a lot below a 1/4th tank of gas did you?

Ninjabread · 03-29-2008, 06:37 AM

Depends which grounds you are talking about? I mean, all the grounds on the wiring harness are good to go.

I just remembered that the FSM has a way to check to see if the pump is dead via resistance.

But either way, I'll just take my pump out of my other car to check.

Ninjabread · 03-29-2008, 09:02 AM

Bah just tested it on my other 240, pump works just fine.

Anyone have any leads? I'm getting 12v at the back (same as my car that runs) but the fuel pump isn't priming.

Ninjabread · 03-29-2008, 10:56 AM

Ok fuel pump decided to miraculously work....

still doesn't start. Onto other things.

aNskY · 03-29-2008, 11:34 AM

coulda just backfed 12v to the pump instead of swapping it twice.. lol.. but anyway- now you have fuel. do you have spark? you said you messed with the engine harness. make sure eveything is plugged in..
also make sure you dont have your line/return reversed (if you had your fuel lines off)

Ninjabread · 03-29-2008, 11:50 AM

haha good point, but it only took 5 seconds either way.

I have fuel pressure now, so I'm gonna check to see if injectors are fireing and to see if i have spark.

JVD · 03-29-2008, 11:58 AM

Quote:

Originally Posted by Ninjabread

haha good point, but it only took 5 seconds either way.

I have fuel pressure now, so I'm gonna check to see if injectors are fireing and to see if i have spark.

I'm willing to bet it will go out again. Haha. I had this happen to me. Shut off my car, went into a store, and when I came out it would crank forever but never start. Tested everything like you did. Even put in a new nismo pump. Thought it was fixed and went around the first corner in my crescent... car just dies. Hahaha.

I ended up putting a new relay and wiring to the pump. Never could figure out the prob. Seemed like something was shorting between the relay and pump. Maybe just a bad ground? I searched and it seemed to be a semi-common problem. Most people just ended up rewiring it like I did.

W/e. Just another reason I'm putting in painless now.

Good luck Bread.

KiLLeR2001 · 03-29-2008, 02:18 PM

Quote:

Originally Posted by JVD

I'm willing to bet it will go out again. Haha. I had this happen to me. Shut off my car, went into a store, and when I came out it would crank forever but never start. Tested everything like you did. Even put in a new nismo pump. Thought it was fixed and went around the first corner in my crescent... car just dies. Hahaha.

Everytime I had this problem, every single time it was the coolant temp sensor being fucked up. When replaced it would fire up everytime. I think it has something to do with dumping too much fuel into the cylinders and won't fire up until you wait till the gas evaporates.

03-28-2008, 07:33 PM	#1
Ninjabread Post Whore! Join Date: Jul 2005 Location: Ottawa, Ontario Age: 32 Posts: 3,492 Trader Rating: (2) Rides Gallery: Ninjabread Feedback Score: 2 reviews	Fuel pump woes Just need some confirmation. Car used to start just fine before I put it away for winter. I fiddled with the engine wiring harness, put it all back together and now it doesn't want to start. It cranks, but no fuel. So I started checking around with a multimeter. I checked the fuel pump signal from ecu, and it gave me 12v, changed the fuse, even checked there, 12v as well. I jumped the 1-3 terminals on the relay to test that out, and no difference (both getting 12v). Go to the back of the car, I unplug the fuel pump harness, test it and the two middle prongs (holes or whatever you want to call them... receptacles?) are getting 12v. *Does this mean my walbro is dead?* __________________ 613DriftWerks.ca

03-29-2008, 12:11 AM	#2
KiLLeR2001 Post Whore! Join Date: Jun 2007 Location: オーランドフロリダ Posts: 7,955 Trader Rating: (46) Feedback Score: 46 reviews	I'm assuming it doesn't prime at all, correct? Did you check all your ground wires? If everything else checks out the pump is the only thing left. You didn't drive it a lot below a 1/4th tank of gas did you? __________________

03-29-2008, 06:37 AM	#3
Ninjabread Post Whore! Join Date: Jul 2005 Location: Ottawa, Ontario Age: 32 Posts: 3,492 Trader Rating: (2) Rides Gallery: Ninjabread Feedback Score: 2 reviews	Depends which grounds you are talking about? I mean, all the grounds on the wiring harness are good to go. I just remembered that the FSM has a way to check to see if the pump is dead via resistance. But either way, I'll just take my pump out of my other car to check. __________________ 613DriftWerks.ca

03-29-2008, 09:02 AM	#4
Ninjabread Post Whore! Join Date: Jul 2005 Location: Ottawa, Ontario Age: 32 Posts: 3,492 Trader Rating: (2) Rides Gallery: Ninjabread Feedback Score: 2 reviews	Bah just tested it on my other 240, pump works just fine. Anyone have any leads? I'm getting 12v at the back (same as my car that runs) but the fuel pump isn't priming. __________________ 613DriftWerks.ca

03-29-2008, 10:56 AM	#5
Ninjabread Post Whore! Join Date: Jul 2005 Location: Ottawa, Ontario Age: 32 Posts: 3,492 Trader Rating: (2) Rides Gallery: Ninjabread Feedback Score: 2 reviews	Ok fuel pump decided to miraculously work.... still doesn't start. Onto other things. __________________ 613DriftWerks.ca

03-29-2008, 11:34 AM	#6
aNskY Nissanaholic! Join Date: Apr 2005 Location: NY Age: 37 Posts: 1,604 Trader Rating: (10) Feedback Score: 10 reviews	coulda just backfed 12v to the pump instead of swapping it twice.. lol.. but anyway- now you have fuel. do you have spark? you said you messed with the engine harness. make sure eveything is plugged in.. also make sure you dont have your line/return reversed (if you had your fuel lines off)

03-29-2008, 11:50 AM	#7
Ninjabread Post Whore! Join Date: Jul 2005 Location: Ottawa, Ontario Age: 32 Posts: 3,492 Trader Rating: (2) Rides Gallery: Ninjabread Feedback Score: 2 reviews	haha good point, but it only took 5 seconds either way. I have fuel pressure now, so I'm gonna check to see if injectors are fireing and to see if i have spark. __________________ 613DriftWerks.ca

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