Half A Tank = Sluggish

[Ki_spirit]

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?

[trel]

fuel pump. mine makes weird noises when it primes when you turn key to on. I think it's on it's way out so I will get a bosch in there soon.

[Ki_spirit]

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.

[tridentt150v]

it would help, but can be delayed

[teng]

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.

[teng]

Hmmm. Whenever i turn the ignition to ON (not START), I hear a weird sound behind my car. Something like what trel mentions. How can you tell if the pump is on it's way out?

[-Dukes-]

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.

[teng]

If it does go, i'll get the nismo one. drop in and easy to replace. Should have similar or close to the same capacity like the tomei one.

Edited July 26, 2008 by teng

[trel]

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]

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.

[bubba]

Get a Bosch 044 and mount it intank. I paid $215 delivered for mine.

[trel]

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]

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.

[trel]

Just grab yourself a bosch 040 pump theyre good for about 300kw. They require little modification to fit and they cost about $150.

[Ki_spirit]

Just grab yourself a bosch 040 pump theyre good for about 300kw. They require little modification to fit and they cost about $150.

Cheers mate. Might get one this weekend let you know how I go.

Sam.

[trel]

Sweet as man. Make a little DIY with pics while youre at it Hopefully can get it stickied. Good luck.

[blck32]

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 August 1, 2008 by blck32

[trel]

I know what priming noise sounds like and humming from the pump. The noise mine makes is a groan which is NOT normal, this is what I/we mean by weird sounds.

Cheers.