Crap. Did I Just Waste My Time With Upgrading The Fuel Pump?

[KrazyKong]

Replaced the stock fuel pump in my R33 the other week. Had troubles with fuel leakage and ended up sorting that out. The fuel pump was a working pull from another car, but not sure how long it sat outside the car. It's the Walbro 294 one that was already mounted in the braket. So the actual fitting part was simple.

But I'm not left with this very high pitched whine noise at both idle and an even louder noise at load. Have been told, duh! that's because it was sitting around and dried out before I bought it. Others have also said that the aftermarket fuel pumps will be noiser.

I havn't put anything else into the car like a fuel pressure regulator or an SAFC. Whatever is stock in a R33 SII Auto is what I still have in mine.

Car has stalled a few times when lifting off the gas and say coasting to some red lights. Those times it started right back up again.

Fuel usage seems not so good to me. In fact my gut feeling is now my car is using more petrol than before. And the funny or sad thing is before I switched the fuel pump, my gas mileage got real good after being told to use BP 98 instead of the regular 91 octane stuff.

Maybe I'm just imaging all of this, but I do know the car has stalled a few times after changing the pump. I don't know why. Also don't know why my gas mileage seems worse than before the change. I've checked countless times and the initial fuel leak when I first did the changeover has been fixed, so it can't be a leak. Also no smell either.

So have a just wasted my time and money here? And suffice to say the working stock pump I pulled out, I've not had it sitting in any petrol either, so it's dried out as well. Now before anyone gets on my case, I've only just found out about all this, so I didn't know at the time I bought the pump, nor did I know to put my old stock on into some petrol.

[TRB-001]

initially i would say if ur using more fuel then before the pump should still be work ok. as for the noise, its abit hard to say without hearing it.

it should be to do with the way its mounted, it should have some sort of rubber dampening where it attaches to the metal bracket. but if its as loud as u say then there is something wrong with it, i would make sure there is nothing blocking the pickup

best thing to do is to get the fuel pressure checked by either putting your own fuel pressure reg with guage on it, or at a workshop

Edited April 21, 2010 by TRB-001

[mad082]

the only way that the fuel pump alter fuel economy was if the old pump was really dead and unable to pump enough fuel. the fuel pump doesn't alter the pressure the injectors see or how much they fire into the cylinder.

as for the noise, generally after market pumps will be louder, but how much compared to what you are hearing is hard to say over the internet.

[Mayuri Krab]

My Bosch 040 pump was much louder than the stock pump it replaced (which had died). The pump constantly makes a whining sound when its on, although most of the time while driving my exhaust sound masks it off.

However I didn't experience any of the other symptoms you have described.

[JoelyMoley]

stalling when shifting gears? sounds like AFM to me, try give it a clean?

[KrazyKong]

Not when changing gears. It's an auto btw too. It stalls when coasting, or having lifted off the accelerator pedal. So it could be coasting to a stop at some lights, waiting to pull in your driveway as the gate is opening etc.