How to tell dying fuel pump?

[rs73]

Just wondering anyone had this sort of problem and how to tell if it's the dying fuel pump and not something else?

My car keeps leaning out even on stock boost.

[DezertEagle]

I had the same problem, not sure if it was dying fuel pump, but it was leaning out severley and lead to me blowing a piston or two.

I recommend just getting a fuel pressure gauge hooked up to your fuel line and see how the pressure is.

[rs73]

well then did u fix ur engine and replace the fuel pump and had another go at dyno? what's the result?

also using fuel pres. gauge, will it still be reading low if fuel line is blocked or fuel filter is dirty? any way to tell straight away?

[unwritten law]

change the fuel filter (if it hasnt been changed in the last ~20 000ks). clean air filter & AFM. Reset ECU. Check timing.

[GTRgeoff]

You can remove the return line and put an extension on it so it can reach a bucket or back to the filler.

Start the car and observe the fuel returning at idle. Bring the revs up and watch the fuel flow. If it is a weak flow at idle and worse at revs with no load then the pump has issues.

Definitely replace the fuel filter first.

[rs73]

The fuel pressure test shows that my car got bad fuel pressure, it's not stable...

I was told this is a common problem in GTS-t & GT-T... GTR fuel pump seems to last longer. Someone on this forum with R34 GT-T also had fuel pump issues and an R34 is at least 5-6 years newer than mine!

[rs73]

Update: I guess it is dying pump after all.... after replacing the fuel pump the engine regains extra 40kw at the tyres with a/f approximately 12:1

[GTRgeoff]

Good news what did you put in? I had no end of overfuelling when I put the GTR pump in but the PFC fixed it.

[rs73]

Bosch975 mounted in tank. SAFC should fix any A/F issues... I thought it should have a stable pressure regardless what pump as it's regulated by the fuel pressure regulator? i only have stock fuel reg. stock ecu. stock turbo. stock airbox.

192rwkw in shootout does sound inflated isnt it? stock ECU. how much diffrence usually between dyno shootout & normal mode? 15kw less? 20kw less?

[GTRgeoff]

You would think that, but I had to wind on almost full static advance to get any power after i fitted it (unheard of and no detonation!!!!) otherwise it would choke on the excess fuel. PFC fixed it.

No idea on the shootout mode question though.