lurching under max acceleration

[serbs]

ok,

under max acceleration the vn series 2 motor is lurching like its starving for fuel?

since this ride was built it has not had a problem, today due to upcoming purchases i have started upgrading.....

i first took off the fuel rail and removed the old fuel reg, taped the end with a threaded barb and re-installed the rail.

i plugged all hoses back in accordingly hooked up the new turbosmart fpr800 fuel reg with guage, the hose off rail into the inlet and the return to tank hooked up to the base which i also double checked the illustration and it is right....

the vacuum hose i hooked up off the elbow, (same one that was hooked up to the old one)

after reconnecting battery, priming...checking for leaks then starting all was fine pressure guage on the reg was a bit unstable but looked about right, 37.5psi

took it for a drive and was all good, then soon as i turned onto m4 and hit it, it started lurching like it was starving for fuel...

took it home and left it running and all looked fine, shut it down to have a closer look at everything and noticed the guages hit 0 immediately after shut down which is weird as the guage i have on the direct line before changing the reg never hit zero, if anything it always went down extreemly slowly.......

has anyone had a problem like this before? cheers for any help.

[soop]

uh, its rooted.

[serbs]

You mean the regulator is rooted? If that's the case isn't it only the diaphragms that get screwed?

[delcowizzid]

its typical aftermarket fuel reg behaiviour ide put it in the nearest bin where it belongs myself LOL or fit the stock reg and run the aftermarket after it if you really need it which you wont LOL

[serbs]

Delco seriously I asked a question, in that I gave a detailed description of the problem. So if you don't mind stop posting your same 2 cents worth on my posts, if you want to feel real important maybe giving a technical solution to the problem I'm having could be a start and make you feel nice and warm inside....if not how about throwing yourself off my posts rather than telling me on 2 occasions to throw it in the bin!

Edit:- LOL

[delcowizzid]

i told you nearly every aftermarket reg does this its just the nature of the beast not made to hold steady primed pressure they tend to fluctuate fuel pressure during cranking as well hence why you run the stock one then the adjustable after it to raise fuel pressure

[VPRob]

this may be way off target but are you running the AC? If the pressure in the AC is getting low it can cause the compressor to switch on and off every couple of seconds causing a hesitation when the compressor cuts in and then a surge when it cuts out. Just a thought cos often diagnosing the cause of a symptom is the hardest part

[serbs]

Nah not running ac and heater hose is disconnected due to me blowing the heater core hehe oops, anyway still can't figure it out, contacted manufacturer and they told me should run fine with efi.....thinking of hooking up old reg and test if there's no prob I'm pulling aftermarket one apart as frankly (and I don't care what criticism I get) (opens can of worms) a 250 dollar plus!!!!! Aftermarket rising rate reg should do a better job than a 25 dollar stock reg (that mind you is stock hence why you cannot adjust the pressure to suited performance changes).......

[delcowizzid]

start the car let it idle pull vacuam hose off fuel reg and adjust pressure to 45-47psi "stock base fuel pressure" put hose back on and test drive.the screw in gauges are not to accurate can read 10psi out when tested so if its better with fuel pressure at 47 but not fixed crank it higher