Jump to content
SAU Community

Can The Battery Kill The Fuel Pump?

R.3.2.G.T.R

By R.3.2.G.T.R,
in General Maintenance

 Share

Recommended Posts

R.3.2.G.T.R Grand Master

R.3.2.G.T.R

Posted
Posted

hi folks,

got a new problem with the car i haven't encountered before.. as a background.. my battery ran flat last week so after getting it recharged at the shop few days later.. i think i can hear det on light load.. i have a wideband wired in and on idle it used to be 14 odd now its constantly low 13 afr.. also when accelerating smoothly i can see my afr dipping into low 12 sometimes 11 on the afr gauge..

my suspect is the fuel pump failing due to the perhaps too much draw placed on it while i was using a semi charged battery.. could perhaps be the FPR, fuel filter or bad earth.. in either case.. im looking at changing the fuel filter and putting fuel pressure gauge in to check pressure this arvo

currently i have a sard fuel pump in there.. no odd noises.. primes fine.. no hesistation from the car.. i do have pretty bad fuel economy of late and car doesn't feel as nippy as it used to.. i have read past thread on dying fuel pump but would like to hear if i have missed anything out, will look at getting it on a dyno for a run but that could take a week

Link to comment
https://www.sau.com.au/forums/topic/408567-can-the-battery-kill-the-fuel-pump/
Share on other sites
R.3.2.G.T.R Grand Master

R.3.2.G.T.R

Posted
  • Author
Posted

good point.. although i only run bp98.. the thing is i dont get the knock light flashing (pfc), so may not be getting picked up but sounds like det.. got half tank left, maybe drain it and put a fresh batch in..

when i had the car at unigroup earlier this year, yavuz did comment that its leaning out a bit at the top but wasnt sure if it was fuel pump or voltage or fpr

t_revz Grand Master

t_revz

Posted
Posted

So it's running richer now than before?

Typically electric motors don't slow down after being subjected to low voltage high current situation unless its absolutely fingered and would barely work at all. But I would imagine all fuel pumps are brushless so makes it even more impossible

89CAL Grand Master

89CAL

Posted
Posted

So it's running richer now than before?

Typically electric motors don't slow down after being subjected to low voltage high current situation unless its absolutely fingered and would barely work at all. But I would imagine all fuel pumps are brushless so makes it even more impossible

Exactly what I thought. It sounds like its running richer if anything now

11-12:1 AFR should be OK under load as long as your tune was done properly

R.3.2.G.T.R Grand Master

R.3.2.G.T.R

Posted
  • Author
Posted

right u are lads, running richer on idle n on boost (seeing low 11's), car never ran this rich so I'm about to clean the afms again n pressure test

not sure what the pinging noise is though, fuel pump -ve is grounded to chassis to bypass fpcm

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Murray_Calavera
      HKS stroker kit step 0/1 or HKS GTIII 2530

      By Murray_Calavera · Posted

      @joshuaho96 Hmm considering the drama you've seen/experienced, have you looked into getting a built complete long motor shipped from Australia?  Considering the AUD is basically monopoly money when compared to the USD, at a glance this seems like a good option?
    • Shoota_77
      R32 GTS-t RB30 sedan

      By Shoota_77 · Posted

      Bloody Skylines, they put you through the bloody wringer! Stick at it! Stunning drag strip BTW! Where is it? Can see part of the name on the slip and probably should just Google it!
    • joshuaho96
      HKS stroker kit step 0/1 or HKS GTIII 2530

      By joshuaho96 · Posted

      I mean the other day I had to walk someone through diagnosing why their timing belt was walking off the cam gears. At least one of the issues was a bent tensioner stud. Local mechanics have found runout on the CAS mechanism causing weird failures. I'm also no saint here I've documented some of the things I've had to learn the hard way. Something I discovered recently is that my CA emissions catalytic converters weren't even welded correctly to align the downpipe to the main cat and they tossed the support bracket that goes from the transfer case to the downpipe to support everything there. I spend a lot of time chasing down these decidedly unsexy problems and the net effect is it feels like I never actually get to the original objective (flex fuel, VCAM, oil control, cooling, etc).
    • r32-25t
      HKS stroker kit step 0/1 or HKS GTIII 2530

      By r32-25t · Posted

      At times with how you make everything sound, all I imagine Americans doing when they see a gtr is standing there looking at it and bashing it with a gun like how a caveman would with a club and hoping it fixes itself 
    • joshuaho96
      HKS stroker kit step 0/1 or HKS GTIII 2530

      By joshuaho96 · Posted

      I think this is just a product of how the US market works for this stuff. Shops are expensive and there's no real way of knowing what kind of results you're going to get, people don't really have the institutional knowledge. I have heard too much at this point to really put faith in anybody "full service" except maybe DSport and they aren't really a full service kind of shop. If you go to the right place I have no doubt they'll get it right for you. Some locals have set it up right but the cost really is nuts and even now they're still fighting issues. And you know I'm a crazy person who thinks things like twin scroll, relatively short low-mount cast headers, PCV recirc to intake, recirculating BOV, right-sized for ~400 whp, MAF load, validating all of that to a standard comparable to OEM test programs, etc are relevant. For what it's worth, multiple local owners at this point have been stuck in a perpetual cycle of blowing a motor -> getting someone to rebuild it -> some missed detail causes the bearings to wipe and spin just outside of break-in mileage or drop valves or some other catastrophe -> cycle repeats. I usually only find out about this because I'm perpetually helping random friends with diagnosing car troubles, Skyline or otherwise. The single turbo stuff if I'm honest is mostly secondary, it just doesn't seem to achieve the numbers in the ~2000-3000 rpm region that I would expect given the results I've seen here or in Motive's videos. I don't really know what we're missing here in the US to be causing this. Lots of people like to emphasize the necessity of finishing the project first and foremost, but I'm not made of money and I can't afford to be trashing a 15k+ USD engine build with any regularity. Or spending my relatively limited garage time these days unable to triangulate problems because too much was changed all at once. Also, even if it isn't a catastrophic failure I would consider spending the cost of single turbo conversion with nothing to show for it to be pretty bad. 
×
×
  • Create New...