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Back Fire / Loss In Revs Under Hard Exceleration?

rhys5169

By rhys5169,
in Engines & Forced Induction

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rhys5169 Mentor

rhys5169

Posted
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ok so it was noticable tonight to post up on here, at around 4000rpm its almost like the car takes the accelerator off, cause i get a drop in revs and a back fire noise.

it only does it every now and then, but it shouldnt be doing it......

the car is stock, apart from 4inch hks dragger cat back exhaust, pod filter, super spark coil pack, nismo S-tune sparkplugs and supposedly a bigger fuel pump?

is it just a case of maybe running too rich? overflowing the car with fuel and choking it??? injectors? spark plugs? im new to the whole skyling thing so any advice much appreciated

if youy need any more info please let me know

cheers

rhys

Jack88 Experienced

Jack88

Posted
Posted

i heard it tonite when you took off,did it in first but not in seccond??id just start with the basics like plugs first.have you checked the condition of them since you bought it?do you know what there gapped to?get a hold of some NGK copper plugs to chuck in here to see if that fixes the prob,there cheap and available from just about any where.

oh and it sure as hell didnt sound like traction control cutting in lol.sounded like you had a Bee R installed :laugh:

tridentt150v Grand Master

tridentt150v

Posted
Posted

I'ts not knocking is it? Don't have an orange light flashing when you put the boot into it?

Otherwise its either air of fuel. I'd get your fuel flow and pressure tested, 10 minutes and say $50 at any reputable garage. At least that would eliminate fuel up to [but not including] the injectors.

rhys5169 Mentor

rhys5169

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  • Author
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no flashing lights, and no knocking i can hear from the drivers seat. im gonna drop into my mechanic tomorrow night and ask him a few questions, it does feel like a fuel issue....

jack, whats a bee R? yeh it did do it in first then i short shifted to 2nd and it was fine :s

rhys5169 Mentor

rhys5169

Posted
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Im guessing AFM, do a diagnostic search on the ecu and see if there are any trouble codes

thanks for the reply but im relatively new to the skyline thing, so if you could describe how i could do that? or is it left for someone with a dyno?

cheers

rhys

Beer Baron Grand Master

Beer Baron

Posted
Posted

yep, I would look at failing fuel pump. or even fuel pump loose in tank. it's quite often very pronounced in 1st gear as you get rapid change in fuel requirement as it ramps onto boost, and the acceleration g's push all the fuel to the back of the tank too.

rhys5169 Mentor

rhys5169

Posted
  • Author
Posted
yep, I would look at failing fuel pump. or even fuel pump loose in tank. it's quite often very pronounced in 1st gear as you get rapid change in fuel requirement as it ramps onto boost, and the acceleration g's push all the fuel to the back of the tank too.

i think you may be right, i just taped up every coil to try that method, it has worked somewhat but now i am only getting it in 1st gear after 4000rpm when i seem to be turning??? it barely does it when going in a straight line in first....

so im leaning more towards a pump loose in the tank?? sound about right? whats my next step from here then?

cheers

rhys

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