Fuel Pump Help

[Ps1Locybe]

Hi everyone

So i have just bought a r33 4 door of a close mate and not so long ago he had a bigger fuel pump put in as an " i owe you job " and ever since every now and then you will be able to hear the fuel pump whirring fairly loudly (i can hear it over the engine) although i usually hear it once i start slowing down and the engine is quiter.

Every now and then it will cause the pump to surge but usually you wouldnt hear the fuel pump or have it surge and it would only make the whirring noise and surge when i was running on a low tank of fuel but i have noticed it does it every now and then regardless if how much fuel is in the tank.

Does anyone know what i can do to fix this?

Should i just get a stock fuel pump?

Any help is greatly appreciated

Ps1Locybe

[Ps1Locybe]

I actually ment to write:

It doesn't always make the sound or surge it usually did it on a low tank but now its doing it randomly regardless of howmuch fuel is in the tank.

P.S my mate said the fuel pump was getting air pockets in the lines causing it to surge or something.

Once again any help is greatly appreciated

[sydking]

My guess It's not a plug and play aftermarket pump, and it was not installed correctly, hence not sitting low enough in the tank.

[Ps1Locybe]

Ok so do you think i should try refitt the current fuel pump myself or get a proffesional to do it or should i just get a stock fuel pump?

Sorry im not very mechanicly minded but im prepared to try anything myself

[Ps1Locybe]

Or more importantly do you think it will cause other problems?

[Ps1Locybe]

It will even make this whirring sound when i am on over half a tank of fuel, i am beginning to think the bigger fuel pump is moving uneeded fuel around causing it to heat up and thats when i can hear the pump, it also has trouble starting up sometimes, i have found that if i turn the key and listen for the fuel pump and try start the car before the fuel pump finished pumping fuel it will start fine but if it finishes pumping then i attempt to start it will struggle and i usually need to give it some gas to help it start, which i shouldn't being an automatic transmission.

Im also thinking a fuel pressure regulator might fix this problem but what us everyones thoughts?

Really need some help on this guys?

Ps1Locybe

[scotty nm35]

Don't touch the pressure reg.

We need more information to help you, what pump is it? Has it been wired to battery voltage like all aftermarket pumps should be?

[Ps1Locybe]

I don't think i have a fuel pressure regulator that im aware of? I ment should i get one?

Sorry im not very mechanicly minded and i bought this car of a friend not long ago so i dont have a very detailed understanding of what happened with the fuel pump, when i asked him in a message he replied:

aw it's like equivalent to a Bosch 040 or a 044 some thin like that it's a decent one.

So i guess im going to have to find out for sure exactly what pump it is and if its properly wired to the battery first?

What can i do if i cant find out solud details?

[scotty nm35]

Stick your head in the tank and take a photo of the pump/wiring then post it up.

[Old Booster]

We need more information to help you, what pump is it? Has it been wired to battery voltage like all aftermarket pumps should be?

noob question but why do aftermarket pumps require this? and is it applicable to Tomei and nismo pumps too?

[Moodles2]

Factory setup switches between 6V and 12V, 6V at idle/low load and 12V for higher load. Aftermarket pumps don't like 6V, and don't perform very well at 12V (infact might be worse than the factory pump). It's only when aftermarket pumps are running at alternator voltage will they deliver what they advertise (255lph for walbro pumps etc)

[Old Booster]

Thanks for the info, I was intending to upgrade my stock pump with a DW200 it has voltage rating of 6-18v do you think it would still need the wiring mod?

http://www.deatschwerks.com/dw200-fuel-pump-tech/

sorry for the thread-jack, Paul hope you're finding the info useful too.

[scotty nm35]

Yes, run the old pump power wire to a relay and switch constant power (fused) from the battery with decent sized wire. Don't forget to do the negative side as well, I run that back to the battery also.