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

    • Rezz
      R35 GT-R production ends after 18 years

      By Rezz · Posted

      Order for the 2025 model R35 GT-R were accepted from 3rd March and 26th August the last order rolled off the production line at the Tochigi plant. Concerning the R35 GT-R replacement, current Nissan CEO Ivan Espinosa said "Nothing has been decided about the GT-R at this time, but we are well aware that everyone is waiting. The GT-R will evolve and reappear in the future. Please be patient until that day comes." Nissan has a lot of issues with management and finances so take Espinosa's words with a big grain of salt. From what discussions I've had and read about here in Japan, not a lot of people are confident about Nissan's future, let alone the next GT-R. 
    • Kapr
      ECU sees many times the speed than speedo does (R34 swap)

      By Kapr · Posted

      Thanks. We getting some parts along too so he will be solving the speed issue like next week so i will let you know what he came up with.   
    • MBS206
      R34 25GT Engine Light 21

      By MBS206 · Posted

      21 is explicitly the coils detected as the issue. Is it guaranteed the actual issue? No. Just the ECU thinks it is. When you say rattling, describe it better, get an audio clip as best you can if possible.
    • CF.Panda
      R34 25GT Engine Light 21

      By CF.Panda · Posted

      Yea got me coppers. Bad news is I just put them in and the car still has the light and shakes. I also noticed I hear like rattling coming from the exhaust piping right under me. Does 21 also have a possibility of being O2 sensors?   So, coil packs are good, the harness is good, the MAF is working, and obviously the spark plugs just replaced and working.
    • MBS206
      RB25DE NEO with Haltech ECU

      By MBS206 · Posted

      Make sure you drop the GTT base tune back in, and set your injectors again, this will remove anything playing up with it you may have removed. Possibly lean there as it's normally a fast transient going THROUGH atmospheric pressure, and a turbo motor would then quickly go richer as boost builds. The only worry you MIGHT have is ignition timing, as the DE is higher compression than the DET from memory. But again, you're not in boost, so the DE motor will be a lot more forgiving at atmospheric.   Get Murray, Kinkstahs, and Johnny's input on tuning haltechs, those guys have played with tuning enough in the past to be able to help now you're past the trouble shooting stage of the MAP issue
×
×
  • Create New...