Is it supposed to hold pressure after you turn it off when its been running? Its set at 35psi base but I could swear it used to hold pressure even after I turned it off, have a feeling its crapped itself?
Can anyone confirm? It's a SARD unit so no cheapy.

mine sits at the set pressure, as you leave the car, the pressure should slowly drop. mine is also a sard!

great, good use of money there. looks like mine is poo. glad im not turbo'd or something ro else id have turbos leaking oil, coolant lines leaking, cracked manifolds, IC pipes blowing off and anything else that can go wrong *insert hissy fit bitch rant about car*

thanks well guess that cleared that up

;1107550']great, good use of money there. looks like mine is poo. glad im not turbo'd or something ro else id have turbos leaking oil, coolant lines leaking, cracked manifolds, IC pipes blowing off and anything else that can go wrong *insert hissy fit bitch rant about car*

thanks well guess that cleared that up

is it slowly dropping, or is it not moving at all?

well when the car WAS running it was fine, turn car off and it'd go to 0. car took ages to start in the morning too. think ill just put a standard one on for now.

Well for what its worth Tuffy, ive had 2 different fuel regs on my magna and both of them have "bled" down over time (about 30mins to a hour). Even the one on our drift car does it.

before you ditch it man just make sure it's not leaking, or it could just be draining back into the tank.... my guess would be that it only works when it's under pressure and probably wont hold it forever.

Also when they put in your fuel pump did they use the original wires or run some new ones?

is there any reaosn you run such such low pressure to start with? Being JDM i would sugget base stock pressure would be much higher, every jdm car ive been through (a few now) run at least 42psi base, some of them being turbocharged, but predomeinetly NA and all were at least 42psi

Well for what its worth Tuffy, ive had 2 different fuel regs on my magna and both of them have "bled" down over time (about 30mins to a hour). Even the one on our drift car does it.

Yep, thats what this USED to do. When I picked the car up the first time would start after 2-3-4 cranks no worries. perfect almost. Now, over 10 cranks, sometimes sort of puffs itself out and you gotta start cranking it again so hmm



before you ditch it man just make sure it's not leaking, or it could just be draining back into the tank.... my guess would be that it only works when it's under pressure and probably wont hold it forever.

Also when they put in your fuel pump did they use the original wires or run some new ones?

Nah it's hotwired mate through the ECU so yeah new wiring. But yeah thought something was up well good to have confirmation.....

Not that raising the base pressure will help if the diaphram is leaking but running more pressure could prolong the time it takes to drop the fuel pressure to a point where it cannot fire and start properly. On NS.com there was a few guys talking about issues with there sards not holding fuel pressure for long periods of time (like the stock item) besides being adjsutable, they are kind of a redundant item, on an SR (which many of my years were spent dealing in) the stock piddly looking fpr was good for consistant fuel pressures up to use with 800cc injectors, obviously if the pump could supply the juice. The magna item looks remarkedly similar to the nissan item in design.

The magna item looks similar to a few diff variants.....I've chucked it in the car in case they come to the conclusion the FPR is cactus

Tuffy, I mentioned this to you when we did your shafts

The aftermarket ones are well known for bleeding down, the best shot is to keep your standard reg and then plumb this one in after your std reg

This way the std reg will hold the pressure and the aftermarket one will then lift the pressure if needed

Also check it is not your fuel pump, the standard pump has 2 things a lot of aftermarket pumps do not.
1/ pulse valve, stops the fuel pulsing through the lines
2/ pressure valve, stops the pressure dropping and the fuel draining back to the fuel tank

Tuffy, I mentioned this to you when we did your shafts

The aftermarket ones are well known for bleeding down, the best shot is to keep your standard reg and then plumb this one in after your std reg

This way the std reg will hold the pressure and the aftermarket one will then lift the pressure if needed

Also check it is not your fuel pump, the standard pump has 2 things a lot of aftermarket pumps do not.
1/ pulse valve, stops the fuel pulsing through the lines
2/ pressure valve, stops the pressure dropping and the fuel draining back to the fuel tank

When I get home tomorrow I'll take some pictures and show you.
Yeah I noticed it too. maybe is the pump? Well....will work it out soon enough...

Maybe hooking the pump upto the the ACC line will let it get some pressure before the motor cranks... pretty sure this is how the VN/VP homodores work

If yours is coming on while the motor is cranking it's probably getting about 8V and not making a whole lot of pressure, this coupled with the pressure leak when it's off would make it hard to start.

Maybe hooking the pump upto the the ACC line will let it get some pressure before the motor cranks... pretty sure this is how the VN/VP homodores work

If yours is coming on while the motor is cranking it's probably getting about 8V and not making a whole lot of pressure.

It primes for 3 seconds (adjustable on ECU) when on IGN so plenty of time for it to prime up. I will work it out though...

The value didn't change recently did it?

Nope checked it tonight... + you can hear the pump prime when you go to IGN

Does the little gauge jump back up to the right PSI?

Also, probably doesn't help that your car is running very rich... Car running rich helped along by the fact your spark plugs are more carbon than metal you probably would have troubles starting.

Does the little gauge jump back up to the right PSI?

Also, probably doesn't help that your car is running very rich... Car running rich helped along by the fact your spark plugs are more carbon than metal you probably would have troubles starting.

front 3 were changed and no difference....there is def something not right in regards to ECU fueling though. seems to change its map willy nilly. I have a peak the size of Mt Everest right now in my fuel map its not good

Get the bastards on the phone and get them to fix their mistake, or ditch the ECU... there is no reason for it to keep changing.

Maybe hooking the pump upto the the ACC line will let it get some pressure before the motor cranks... pretty sure this is how the VN/VP homodores work

If yours is coming on while the motor is cranking it's probably getting about 8V and not making a whole lot of pressure, this coupled with the pressure leak when it's off would make it hard to start.

NO DO NOT DO THIS

Is highly illegal and damned dangerous

The fuel pump HAS to cut if there is an accident for safety, thus why you have relay's etc

You will get a 3 or so second pulse on ignition turn and then it will cut unless the engine is cranked and the engine fires and the ecu registers an ignotion pulse

Paul, to check, pressurise the system, shut down the car and block off the main fuel line, if pressure holds then the pump is bad and the reg is good. If the pressure still drops, do the same and after shut down block return line, if pressure then holds then the reg is to blame

NO DO NOT DO THIS

Is highly illegal and damned dangerous

The fuel pump HAS to cut if there is an accident for safety, thus why you have relay's etc

You will get a 3 or so second pulse on ignition turn and then it will cut unless the engine is cranked and the engine fires and the ecu registers an ignotion pulse

Paul, to check, pressurise the system, shut down the car and block off the main fuel line, if pressure holds then the pump is bad and the reg is good. If the pressure still drops, do the same and after shut down block return line, if pressure then holds then the reg is to blame

more VN's should do this, might result in a few more off the road....

If the weather aint CRAP tomorrow I will give this a go, do you mean block it with like what just hand or something after the reg yeah?

If you have rubber hose, use a tool made to block the hose, is usually 2 round bars that clamp together so no damage to the hose

If you have rubber hose, use a tool made to block the hose, is usually 2 round bars that clamp together so no damage to the hose

Seen them....I know what your talking about but the shops will close before i get a chance to visit em tomorrow.

bah. Next time im gonna run a standard 3L ecu and an SAFC ii with wideband would of had the car going 6 months ago.

You can use vice grips if you are careful mate, just dont pinch the line

You can use vice grips if you are careful mate, just dont pinch the line

After my luck with....well....everything.....Might leave it for the workshop to digest...

can someone please tell me the stock fuel pressure at warm idle vacuum on and off?

looking to get an afpr to play with as a few of the dyno sheets here i see for stock seem to be running a tad rich... gonna dyno mine to confirm and make adjustments for hopefully a tad more power.

Thanks in advance.

DSP26 you know that without a fuel map tune or full tune, only lowering the fuel pressure will net less richness, and maybe some more power. The higher the fuel pressure, the more fuel is squeezed out; so without tuning the injector pulses, this will richen up the fuel mixture not lean it out

Have you contacted Jason yet Paul?

Have you contacted Jason yet Paul?

Had a chat to him yesterday, workshop will go over the car tomorrow and let me know what the result it and we will work from there on.

DSP26 you know that without a fuel map tune or full tune, only lowering the fuel pressure will net less richness, and maybe some more power. The higher the fuel pressure, the more fuel is squeezed out; so without tuning the injector pulses, this will richen up the fuel mixture not lean it out

i know exactly how it works and on the dyno sheet... it will move the entire a/f curve up or down as it doesn't tune individual rpm points... i've tested it and the pulse doesn't matter too much on a minute change. Reducing?increasing fuel pressure will still reduce/increase AF ratio regardless of pulse and duty cycle. If anything tuning ignition timing makes more of a difference.

Just hoping i can find a good 'average' without going too lean or rich in some spots.... because on my SR20 motor it netted excellent results without tune... the A/F ratio wasn't too lean at the lower rpms but too rich at upper rpms... by reducing the fuel pressure a mere 2psi i was able to get the lower rpms maxed out at only 14:1 A/F and i managed to get the upper rpm into the13-12.5:1 range which was the sweet spot for the motor.

By the looks of the dyno thread in the 3rd gen section here i maybe able to pull off something similar and possibly better results than in my 4 banger... FYI in the sr20 setup i managed to get ~4wkw between midrange to topend just by leaning the fuel with an AFPR.... but then again i was running 11:1CR and a Crane Cams LX91 coil with iridium plug gaps at 1.8mm...BUT the power gain was from leaning alone... but the gain was huge POSSIBLY because of my other mods.


***EDIT***
soooo.... can someone please enlighten me with the vac on/off fuel pressure at warm idle? Thanks

Well the workshop reckons the diaphragm isn't sealing properly or something....

Anyone know if I can get a rebuild kit for them or?

;1112443']Well the workshop reckons the diaphragm isn't sealing properly or something....

Anyone know if I can get a rebuild kit for them or?

most of the time an afpr's diaphragm isn't the issue, it's the spring that sags preventing the seal

theres no kits per say since the actual diaphragm is just a piece of metal, they get 'rebuilt' the same way a blow off valve does which is pretty muc that round metal piece, a spring and rubber seal

***EDIT***
open it up and you'll see what i mean... i think their just allen screws holding them

I only paid $60 for it 2nd hand But it DID work (It wasnt defective when i got it)

Who would rebuild such a thing?

I wanna keep it looks ace lol

;1112460']I only paid $60 for it 2nd hand But it DID work (It wasnt defective when i got it)

Who would rebuild such a thing?

I wanna keep it looks ace lol

not hard, you can goto any metal fabricator to make you a new diagphragm from steel if you want but like i said its usually the spring that gives.

but i know what you mean, i've bought a cheapo Type RS replica blowoff valve from eBay.. functioned and sounded as per the real thing except the diaphragm was made of cheap alloy which bent under boost... got it replaced. was a bargain consideirng the real thing was like $400 and i paid $80 delivered from the US.

I would say "I totally understand" but this is a genuine SARD Unit! so it's not a knockoff! Might just use the standard reg for now, Meh....was fun while it was working :(

^^^yeah i know but that wasn't the point i was trying to make, an afpr is a simply vacuum mechanical device very similar to a bov... take it to a shop that sells them as i'm sure genuine rebuild parts can be sourced if that is what you are after, otherwise a performance workshop who can disassemble it to properly assess and replace whichever is faulty inside

^^^yeah i know but that wasn't the point i was trying to make, an afpr is a simply vacuum mechanical device very similar to a bov... take it to a shop that sells them as i'm sure genuine rebuild parts can be sourced if that is what you are after, otherwise a performance workshop who can disassemble it to properly assess and replace whichever is faulty inside

No no understood what you meant :D

Guess I'll talk to the shop tomorrow or keep an eye out on ebay!

PM sent...

Would it harm the tune in any way if I just use a OEM Fuel pressure reg for the time being?

;1114249']Would it harm the tune in any way if I just use a OEM Fuel pressure reg for the time being?

What pressure were you running through the SARD? How much higher than stock?

What pressure were you running through the SARD? How much higher than stock?

Base idle was about 35psi.