noisy fuel pump and car stalling sometimes

[Salar]

Hi,

i just had my stock R32 GTS-T fuel pump swapped for an R32 GTR pump by a shop as well as GTR injectors and resistor pack installation.

today i got the car back and noticed there's a fairly loud whine coming from the tank. the pump i got was used, actually got it from a member here. now i am afraid the pump may be going out. is the noise necessarily a sign of the pump dieing?

also as of last week, with the older pump, car sometimes died while idling, or sitting at red lights, but started off right away. and then tried to stall while in 1st or 2nd gear. it looks like i can't drive a manual car for ****, but it's just the fuel that keeps cutting off i think. any ideas what the cause could be?

tonight after the pump, injectors, and the "tuning" my car received, it still did stall a couple times.

[Spencer87]

You might want to consider cleaning MAF with Contact Cleaner and resolder the connections inside the MAF (the black box).

http://forums.gtrcanada.com/gts-tech/46978-random-throttle-issues-r33-gtst.html

Not sure about the whining though.

[gtrjon]

check you plugs and your maf for the stalling! but the whining should be your fuel pump priming. i dont remember gtr pumps being noticably loud but if you have a walbro or any aftermarket fuel pump when you prime your engine you can hear the fuel pump "whining" or priming.

[bellis_GTR]

Yeah was just about to say if its an after market pump its definitely gonna be noisy.

[Salar]

it was sold to me as an OEM R32 GTR pump. it did say Nissan and made in japan on it i think.

i did my spark plugs about two weeks ago. didn't gap them though. and i'll clean the MAF soon.

thanks folks.

[Shift]

Hook up an inline gauge, if you have access to one, and watch your fuel pressure during starting, revs and idle.
It definitely sounds like the pump is dying.

[nelsonmxmarc]

Gtr pump is SIGNIFICANTLY noisier than stock.
When you tap the gas the voltage regulator will spike the pump to 12 v or so, making it notably louder.

As for stalling.. Are you monitoring your afr's at all?

Also whomever tuned your car may have played with the injector latency and opening duration.. Could be an issue

[Salar]

nelson, you nailed it. it's noisy at idle and then when i give it gas it goes even louder. i am thinking the pump is ok.

yes i do monitor my afr. sometimes it reads 14.5-14.9, and then sometimes after a 30 min drive it's over 15, or even 15.5

the thing is as i said it did stall and try to stall before the tuning, fuel pump and injector swap. now it's actually less happening. i am thinking the prob might be the MAF. the turbo is gt2871 and maybe it's the time to go for a Z32 maf. and for some reason my turbo keeps boosting up. i bought the turbo brand new and the shop who installed it for some reason ****** it up. i'm no expert i don't know what's missing or wrong in there, but it's really depressing after all the money i spent, i can't even go full throttle or past 4500 rpm, because by there i am already hitting 16 psi on a stock RB20.

[Skym]

Sounds like boost cut settings (MAF) because ECU could be running off the fuel, ignition maps. Always seems to happen around 4500rpm on R32 RB20DET ECU. The safety revlimiter is at 5000rpm.

[Salar]

^so which issue are you speaking off right now? the stall problem?

[Skym]

Not reving past 4500rpm. Just found out there's a revlimiter for speed and engages at 4400rpm if getting no speed signal to ECU from dash. It seems to be separate from the safety revlimiter, boost cut.

[blkgtr02]

fuel pump is normal. I replaced mine w/ a new oem pump and it still whines.

[Skym]

Fuelpump on my car is quiet. Can hear it quietly prime before starting, but that's about it. Same on my mates GTR racecar that's quiet throughout powerband when voltage increases.

Fuel pump can start whining when fueltank is run low and it damages fuelpump due to starving fuelpump of fuel and picking up crap on bottom of fueltank that could block sock on fuelpump or engine bay filters. I rarely run below 1/4 tank because of this problem. Not changing fuelfilter in engine bay is another cause of fuelpump failure (often not changed since factory, but should be changed every 20,000km or so and fuelpump replaced every 100,000km as part of routine maintenance).

For example with a Walbro fuelpump and is usually the result after running fueltank low -

http://www.youtube.com/watch?v=A7-h_GP0J7U

But external fuelpumps can create a whine noise, like on Big Bird R33GTR (used in the 1st Fast N the Furious movie) -

http://www.youtube.com/watch?v=SIFNA7_2mGU

[Chewy]

my guess is it's overfueling... more fuel pressure and larger injectors with no management to dial back the amount of gas she's getting off boost. Especially if you're coming to a stop after boosting, you'll have a bit of a fuel pressure spike with the stock fpr. Despite the stock fpr being able to handle some fairly high pressures, it will see a bit of a spike when you come off heavy throttle sharply; paired with the injectors, it seems like a no brainer that it'd be overfueling. Can't hurt to do what others suggested as it will only help, but I'm pretty sure that's what it is.

[Salar]

my guess is it's overfueling... more fuel pressure and larger injectors with no management to dial back the amount of gas she's getting off boost. Especially if you're coming to a stop after boosting, you'll have a bit of a fuel pressure spike with the stock fpr. Despite the stock fpr being able to handle some fairly high pressures, it will see a bit of a spike when you come off heavy throttle sharply; paired with the injectors, it seems like a no brainer that it'd be overfueling.

i think you've pretty much got it right there. it does turn off at random stops, sometimes after boosting, sometimes just normal driving. and then other times it shoots fire.
now does this mean the car is not tuned properly? should i go for an aftermarket fpr? and also lately i've noticed my afr reads around 10/9-12/5 at idle which is fairly lean. is this going to damage the engine?



Skym, you misread my post. i didn't say it doesnt rev past 45000 rpm. it goes past but it also keeps boosting up. the boost doesnt stop. so i've hit almost 18 psi just around 5K rpm, obviously i stopped it there.