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Half A Tank = Sluggish

Ki_spirit

By Ki_spirit,
in General Maintenance

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Ki_spirit Contributor

Ki_spirit

Posted
Posted

Hi,

Ever since I have had my car (4 months), I have noticed it behaves differently as the level of the tank changes. Around half way, it seems to run rich (sluggish) and goes through the fuel FAST. When almost full and getting low, the car seems to run leaner and respond well to boost and spools up quickly, responsive and alive?

It's an r33 skyline S1 by the way.

What could it be?

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teng Rising Star

teng

Posted
Posted
Think I might go with something like a Tomei Fuel Pump - 255L/H for skyline. Do I need a tune after the new pump is installed if using the same regulator?

Thanks.

How exactly do you tune a fuel pump? If you install a large fuel pump with stock injectors, there are gonna be issues as the pump wull not fully be filled before going to your injectors. I may be wrong.

-Dukes- Proficient

-Dukes-

Posted
Posted

Yeah could be mate, I'd replace it to be safe.

Mine went without warning, My R33 s1 wouldn't start at Autoone one day, so I tapped the bottom of the tank to get her started and speed home. $180 for a walbro 400hp ( I think thats the brand?) and 30 minutes to install it myself.

They are piss easy to replace. Theres a guide on here somewhere.

trel Mentor

trel

Posted
Posted

I wouldn't waste my money on a brand like that. It just pumps fuel. A bosch 040 or 044 would do the trick. I only say bosch as it is a proven good brand and not too expensive either. Walbro isn't too bad depending on how much modification you want to do, but I hear they dont last anywhere near as long as a bosch. I am changing mine next week just for safety's sake anyway. Car starts properly and all, but I dont like the weird noise it makes sometimes when it primes.

Cheers.

Ki_spirit Contributor

Ki_spirit

Posted
  • Author
Posted

I get the weird sounds when I am starting my car, and the pump is priming; but - I also getting a raising electronic sound from the pump when slightly lifting the rpm above idle.

Looks like it's time for a new pump.

Where can I find these bosch pumps for a decent price you mention trel?

Walbro isn't too bad depending on how much modification you want to do

And what do you mean about 'modifications' with the Walbro - mods to the pump itself or engine wise?. I here the Walbro's are made to operate at 15v? - Does anyone know if the flow will be fine at 12v or does the voltage need to be raised?

Noob question = How can my car get tuned with stock ECU and uprated fuel pump?

From what I'm thinking it can't be done without an aftermarket ECU (eg.Power FC) - Will an SAFC suffice?

Thanks everyone.

Sam.

trel Mentor

trel

Posted
Posted
I get the weird sounds when I am starting my car, and the pump is priming; but - I also getting a raising electronic sound from the pump when slightly lifting the rpm above idle.

Looks like it's time for a new pump.

Where can I find these bosch pumps for a decent price you mention trel?

And what do you mean about 'modifications' with the Walbro - mods to the pump itself or engine wise?. I here the Walbro's are made to operate at 15v? - Does anyone know if the flow will be fine at 12v or does the voltage need to be raised?

Noob question = How can my car get tuned with stock ECU and uprated fuel pump?

From what I'm thinking it can't be done without an aftermarket ECU (eg.Power FC) - Will an SAFC suffice?

Thanks everyone.

Sam.

Ok well, bosch pumps can be found anywhere, repco, bursons etc. Try Kudos Motorsports on here he has them pretty cheap.

Modifications with Walbro I mean engine mods, I hear they shit themselves easily. The bosch pumps are best by what I hear.

You can get your car tuned with stock ecu by doing a re-map on it. SAFC is a fuel cut defender. Why do you want an SAFC? Are you getting fuel cut issues with your car?

Hope this answers some of your questions.

Ki_spirit Contributor

Ki_spirit

Posted
  • Author
Posted
Ok well, bosch pumps can be found anywhere, repco, bursons etc. Try Kudos Motorsports on here he has them pretty cheap.

Modifications with Walbro I mean engine mods, I hear they shit themselves easily. The bosch pumps are best by what I hear.

You can get your car tuned with stock ecu by doing a re-map on it. SAFC is a fuel cut defender. Why do you want an SAFC? Are you getting fuel cut issues with your car?

Hope this answers some of your questions.

Hi mate,

No fuel cut issues with the car at the moment. I think the ecu has been remapped and wiring loom has been modified - posted a thread a while back 'What the hell is this?!'. As per running the stock pump, which I think is going to go soon, I am anticipating a decrease in air: fuel ratio which I think can be resolved using an SAFC to moderately tune the engine due to the increase in pressure with the new pump, due to the fact the car was remapped with a dodgy pump.

How much do the bosch's go for? - I am looking for a direct in-tank replacement.

Thanks.

Sam.

blck32 Enthusiast

blck32

Posted
Posted (edited)

ok there is a DIY on how to install the bosch 040. They are a good pump, but i dont know what you lot are complaining about the priming noise. ALL good pumps will make the noise when u turn the key on. My 040 humms all the time, i have done the 14v mod to it too.

Just cause ur fuel pump makes a noise it is in no way stuffed.

EDIT Written by: Choku_Dori

Edited by blck32

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