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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

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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

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

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

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

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