GoodfellaFD3S

iTrader: (213)

Yes, I searched

I'm running an Apex'i BNR fuel pump, stock wiring. It's been bulletproof, probably has 10k miles of use on it.

When I had my FD down at the Tail of the Dragon, every time I ran the car hard through the dragon (11 miles, 318 curves) when I came out on the other end and let the car cool down, the pump was buzzing audibly, it could be heard from the driver's seat. When I rev'ed her in neutral, the buzzing got louder.

I always ran through on a full tank of gas, at it's lowest point I had 3/4 tank.

My FD drove fine, I have an in-car fuel pressure gauge and there were zero problems at all. peak fuel pressure was around 4 bar. If not for the buzzing, everything was fine.

It happened four times, each time going through the dragon. Hasn't happened since, to include the 730 mile trip home. It also happened to my friend Garret/G's third gen in his FD, walbro with stock wiring.

The RE-Gorilla mechanic/rotary stud on hand surmised it was a bad fuel pump relay, which is a possibility. I'd rather not get rid of the pump, as it was pretty damn pricey and has worked very well.

thoughts?

hsitko

iTrader: (1)

I wonder if its not specifically the pump, but say something near it. If you are driving it like i think you are through the dragon with peaks of 4 bar, perhaps it is something near the pump that is causing the buzzing. Either that or i wonder if it is some of that strange water hammer effect that the stock system had the fpd on there to get rid of? I'm wondering if i might soon be hearing the same thing. I would hate to think that your pump is bad seeing as how that is supposedly one of the best pumps on the market.

All that said, it could be that you dont have a bad pump, but perhaps you are overheating it. If you are running outside that pumps efficency range you may be working it too hard. I dont know anything about the specifics of that pump but i bet you have 1600cc secondaries and xx primary injectors running a pretty decent duty cycle at full load higher rpms. That is probably a pretty substantial pressure drop for any pump to contend with. You may just be overworking the pump. The drive home was probably you taking it easy huh? Just thoughts to get your mind turning.

gracer7-rx7

iTrader: (16)

I'm of no help but Crispy posted some really nice write up on fuel pump wiring. I can't find it on his site but I'm sure he can provide a direct link if you PM him.

gracer7-rx7

iTrader: (16)

Found it
http://www.reganrotaryracing.com/fddualfuelpumps.htm

Uncle Hungry

iTrader: (2)

I've had the same problem with walbros and typically it's just an early sign of a dying pump. At least in my cases it was.

fendamonky

iTrader: (6)

^ I hope not.. my bosch 044 has buzzed since the day it was installed, I always figured it was just normal for the beefy aftermarket types.

G's 3rd Gen

iTrader: (11)

I was having the same problem right along side Rich on the Dragon ( I think his gremlins jumped into my tank!). Mine started the second day we were there. I have an old school Walbro 255 (not a knockoff) w/ 15,000 on it. It is directly wired to the battery w/ a relay. We were kicking the idea around of the recirculated fuel getting too warm accelerating or variating the load of the pump. Although I dont see how the temp. of the fuel could theoretically do this . After running the car extremely hard for extended periods the fuel pump would work harder (become louder) if we blipped the throttle at idle to certain higher rpms. It was not voltage related as it was constant according to my computer display.

mad_7tist

bad fuel pump relay seems like a quick jump without looking at the pump voltage.
G's the voltage readout on the commander has nothing to do with the voltage the pump. any chance that all that heavy side to side loading kicked up some crap in the tank and it is partialy restricting the inlet sock or even the fuel filter? unless the housing or your mont for the pump got tweaked and it is buzzing/vibrating.

Fritz Flynn

iTrader: (263)

Hi Rich,
When it gets hot it buzzes. It was always audible in the track car. If and when it stops buzzing when it gets hot that's when I'd worry hehe. Just keep an eye on the pressure gauge and when they can't handle the heat in the kitchen you'll see a slow pressure loss under heavy boosting.

Uncle Hungry

iTrader: (2)

No that's normal, I'm talking about it getting louder over time. 044 is a bad *** pump btw.