Fuel Pump Earth - GT-R Register - Official Nissan Skyline and GTR Owners Club forum

Sniper gt · 13th July 2006, 12:05 AM

I have an R32 GTR with a faulty fuel pump earth. Im guessing the earth wire runing into the top of the petrol tank has broken down somewhere.

My question is can I cut this wire and just run a new earth to somewhere in the back of the car without any problems?

RH9 · 13th July 2006, 12:37 AM

Probably a faulty fuel pump ECU (located behind R/R passenger armrest trim panel).

I had the same problem on my 32 GTR so rather than replace a part I dont think the car needed (it regulates fuel pump voltage hi/low) I just bypassed it and gave my fuel pump battery voltage

I could well be wrong though.........a wire could break anywhere I guess.

Good luck

kennyc · 13th July 2006, 07:12 AM

what does a faulty fuel pump earth cause?

Sniper gt · 13th July 2006, 09:06 AM

Does that fuel pump ecu operate on the live or the earth? Would have thought it would be the live.

Quote:

Originally Posted by kennyc

what does a faulty fuel pump earth cause?

A faulty fuel pump will prevent the pump from pumping. I think in my case the earth wire is broken somewhere because it seems to be an intermitant problem.

Ian C · 13th July 2006, 10:21 PM

I had intermitant fuel pump problems on my old GTI-R........Problem got worse and worse until one day it completely failed.
I believe that the uprated pump (from a GTR) was drawing a larger current.......this resulted in one of the loom connectors (under the back seat) had got too hot and melted.
i chopped both looms and rejoined them and it was fine. Car was sold months later and thankfully the concern hadn't moved to the next connector!

Never know, could be similar problem!

Ian

RH9 · 14th July 2006, 07:20 AM

Quote:

Originally Posted by kennyc

what does a faulty fuel pump earth cause?

Sorry I prob wasnt 100% on the mark with my earlier comment.

When the fuel pump ECU faults it can prevent the pump from getting maximum amperage or possibly voltage - thereby stopping it from delivering its required output?? (apologies my electrical skills are limited)

End result is your fuel pump is stuck in "low fuel delivery mode" when its suppossed to be in "high delivery mode" - like my car was.

I'm not sure what the fuel pump ECU uses to switch between the 2 but it could quite possibly be rpm and or air flow meter voltage.

My car was seriously lacking power about 4500rpm and when I put an AF meter up the exhaust was horrified to find it was running a mixture of 16.2:1 on full boost!! Due to my squish areas being removed from my cylinder head my engine wasnt detonating but EGT's were through the roof

I was very lucky that stupid ECU didnt cost me my motor. I suggest any older R32 owners should bypass it. Wouldnt want it to play up when your flat out in 5th gear. Melted pistons here I come :P

GTR RICH · 14th July 2006, 09:12 AM

http://www.stealth316.com/2-fuelpumpvoltage.htm useful info

13th July 2006, 12:05 AM	#1 (permalink)
Sniper gt GTR Register Member Join Date: Mar 2006 Location: IRELAND Posts: 13	Fuel Pump Earth I have an R32 GTR with a faulty fuel pump earth. Im guessing the earth wire runing into the top of the petrol tank has broken down somewhere. My question is can I cut this wire and just run a new earth to somewhere in the back of the car without any problems?

13th July 2006, 10:21 PM	#5 (permalink)
Ian C Elitetech Automotive Join Date: Jun 2003 Location: Buckingham Posts: 1,293	I had intermitant fuel pump problems on my old GTI-R........Problem got worse and worse until one day it completely failed. I believe that the uprated pump (from a GTR) was drawing a larger current.......this resulted in one of the loom connectors (under the back seat) had got too hot and melted. i chopped both looms and rejoined them and it was fine. Car was sold months later and thankfully the concern hadn't moved to the next connector! Never know, could be similar problem! Ian __________________ +10 extra bhp for £55.... Get your baffled TWIN TURBO pipe now from GTR.co.uk Shop My project

Thread Tools
Show Printable Version Email this Page
Display Modes	Rate This Thread
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode	Rate This Thread:

13th July 2006, 12:37 AM	#2 (permalink)
RH9 GTR Register Member Join Date: Jun 2003 Location: Auckland N.Z Posts: 85	Probably a faulty fuel pump ECU (located behind R/R passenger armrest trim panel). I had the same problem on my 32 GTR so rather than replace a part I dont think the car needed (it regulates fuel pump voltage hi/low) I just bypassed it and gave my fuel pump battery voltage I could well be wrong though.........a wire could break anywhere I guess. Good luck

13th July 2006, 07:12 AM	#3 (permalink)
kennyc GTR Register Member Join Date: Aug 2005 Location: Scotland Posts: 497	what does a faulty fuel pump earth cause?

14th July 2006, 09:12 AM	#7 (permalink)
GTR RICH GTR Register Member Join Date: Oct 2005 Location: Medway Posts: 1,274	http://www.stealth316.com/2-fuelpumpvoltage.htm useful info