Can Anyone Tell Me How The Car Runs With A Failing Fuel Pump Or Regulator ?

[shajar]

Guy's i'm thinking of replacing my fuel pump as am dammed if I can work out what my S2 R33 GTS-T's problem is.

Car has following mods:

• Full 3" exhaust
  
• FMIC
  
• HKS Pod filter
  
• Central 20 ECU
  
• Apexi SAFC 2
  
• RS type BOV copy
  
• Turbosmart boost control running 10psi
  
• Dyno tuned produced 206RWKW with an arching coilpack
  

It's stalling after a little stab of accelerator sometimes hunts for idle indesciminately and lately I've noticed it's loosing power down low then picks up when you give it a boot full to get it going, it does not like hills, my driveway is steep and it only just makes it up (struggles all the way lack of power) then half the time just dies when I pull into garage on flat. It kind of cam good for a while after swapping out the AFM but with all the damp weather seems to have gone back to it's crappy running self. It laso feels like the brake is being applied a lttle when you take your foot off the accelerator, does not seem to coast if you get my drift.

Fuel economy is really good so quite sure not the 02 sensor.

Oh and after got back from dyno tune the tuner advised he took out excessive fuel under 3000RPM and had to put more in from there on, he said the injectores were not flowing much after around 6300RPM

Over some time it has been progressively getting worse, I have done the following to date.

• Replaced Plugs gapped to .6
  
• Replaced coilpacks which fixed a breaking down issue on dyno tune at 4800-6000
  
• Replaced AFM with secondhand unit said to be good when removed
  
• Installed SAFC-2 and had dyno'd
  
• Cleaned AAC valve
  
• Swapped out BOV for standard
  
• Checked for airhose leaks - none evident
  

I am at a point where I may have to spend big bucks with a local tuner (not many reputable ones to choose from in Cairns) to find this issue and I know they will be doing the same as me without alot of technical expertise on these cars, just using the "process of elimination method" and saying to me we need to swap this out then that then this and hopefully jag it.

What does a failing fuel pump or regulator feel like to driver with can anybody tell me?

Edited March 26, 2008 by shajar

[NYTSKY]

Mate,just take the car to you tuner and they will fix it up,better than spending money on things that dont need to be replaced.

[shajar]

True NYTSKY but think I'll have to save around $1500 bucks before even booking it in, seems to be the going rate for replacing anything at all including dyno/tune time..!

[Godzilla32]

One answer...Master fuel gauge!

Hook it up and look for about 250-300Kpa of pressure and about 50 more when you disconnect the vacuum supply line to the regulator. That will confirm whether or not either of your suspected parts are infact problems.

[Bumblebee]

failin fuel pump would cause it to not run very well.. that means adding more revs and boost = less chance the engine will run. a leaking regulator introduces fuel into ur inlet via the vac lines.

doesnt sound like its fuel related but im not there to physically inspect it

[shajar]

One answer...Master fuel gauge!

Hook it up and look for about 250-300Kpa of pressure and about 50 more when you disconnect the vacuum supply line to the regulator. That will confirm whether or not either of your suspected parts are infact problems.

Hhhmmmm spewin sounds like a trip to the mechanic with a Master Fuel guage not so easy to come by...

The weird part of it for me is the way it struggles at idle (starts hunting) or when taking off slowly on any hill the steeper the incline the worse it gets??

Edited March 26, 2008 by shajar

[Bumblebee]

fuel press guages r easy to come by what r u talkin about hahah, local tool shop dude. but it doesnt sound like fuel.. sounds more like a vac leak with the hunting...