Power Drop!
YCEE
11-14-2001, 01:23 PM
I have put this on SDU forums b'fore, but just wants to know more.
My car seems to suffer from this power drop on and off, where the EGT will rise and the Apexi Timer A/f value will show lean when it happens. I took it to a performance workshop and they change the fuel filter and iridium plugs, and they also suggested that it might be a weak fuel pump not delivering enough fuel.
How can I know that the fuel pump is weak? Can I put some sort of fuel monitor device in dash, say like the fuel pressure gauge? I don't want to waste money to replace a racing fuel pump but get back the same problem... as some others suggested that the car might be just too hot that's why it's dropping power. (Anyone could explain why is it showing lean, does the mixture burn leaner when it's hot?)
My car seems to suffer from this power drop on and off, where the EGT will rise and the Apexi Timer A/f value will show lean when it happens. I took it to a performance workshop and they change the fuel filter and iridium plugs, and they also suggested that it might be a weak fuel pump not delivering enough fuel.
How can I know that the fuel pump is weak? Can I put some sort of fuel monitor device in dash, say like the fuel pressure gauge? I don't want to waste money to replace a racing fuel pump but get back the same problem... as some others suggested that the car might be just too hot that's why it's dropping power. (Anyone could explain why is it showing lean, does the mixture burn leaner when it's hot?)
DVSNCYNIKL
11-14-2001, 01:27 PM
If it is the fuel pump, then there is really no way. If the car is not getting fuel, and it is definite, then you need to replace it. However, I'm only saying this as in general information as I do not own a Skyline. If it's because your car is running hot, maybe a bigger or better intercooler is in order.:)
SlowGts-t
11-14-2001, 01:58 PM
If it is intermitent, could be the fuel pump.
If it show lean then there must be not enough fuel getting into the engine. Plugs, timing etc wouldnt cause a lean condition I think, maybe detonation, but not leaning out.
Stick on a fuel pressure gauge in-line after the fuel rail, then using a pair of plier, squeeze (block off) the return line.
Fuel pressure should go from 50psi to about 80-90psi consistently and instantly. If it doesnt then the fuel pump is sad.
If it show lean then there must be not enough fuel getting into the engine. Plugs, timing etc wouldnt cause a lean condition I think, maybe detonation, but not leaning out.
Stick on a fuel pressure gauge in-line after the fuel rail, then using a pair of plier, squeeze (block off) the return line.
Fuel pressure should go from 50psi to about 80-90psi consistently and instantly. If it doesnt then the fuel pump is sad.
YCEE
11-14-2001, 02:10 PM
If I were to stick a fuel pressure gauge in dash, will it show that the fuel pressure is dropping when the fuel pump is slowing down?
DVSNCYNIKL
11-14-2001, 02:12 PM
It should. But you wanna know if your pump is bad, don't worry so much about the fuel pressure guage now. Get that after you fix your problem.:)
YCEE
11-14-2001, 02:36 PM
What if it is NOT the fuel pump? I suppose putting a fuel pressure gauge is far more cheaper than replacing a fuel pump... By the way what is the flow on the standard GTR fuel pump?
YCEE
11-15-2001, 03:34 AM
Can I replace the original fuel pump with a high flow fuel pump without any mods to the injectors?
YCEE
11-20-2001, 01:20 PM
I try to drive the car hard with the air-conditioner on, and the car runs fine, drive it hard with the head-lights on, and it runs fine too, drive it with both the head-lights and air-conditioner on, it runs lean after 10 minutes of driving, what does this suggests?
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