5k rpm problem

[Thanielson]

ok so here id in full detail what is going on. At 5k rpm give or take a few hundred rpms no matter what gear im in the injectors go from arond 70% to 3% basicly stoping all power to the car. anyone any idea what mite be causeing this i dont have a fpr or gauge hooked up to watch the fuel pressure.

neo rb25det, hybrid front mount, apexi gt exhaust, no cat,K&N air filter,ngk irid plugs are the stats if that helps any.

[Joe]

does it happen at partial throttle as well as wide open?

[Oki_R33]

ok so here id in full detail what is going on. At 5k rpm give or take a few hundred rpms no matter what gear im in the injectors go from arond 70% to 3% basicly stoping all power to the car. anyone any idea what mite be causeing this i dont have a fpr or gauge hooked up to watch the fuel pressure.

neo rb25det, hybrid front mount, apexi gt exhaust, no cat,K&N air filter,ngk irid plugs are the stats if that helps any.

what ECU are you running?

[Thanielson]

it happens at both that i know i think.

that i know of it is the stock neo ecu.

[Cjmartz2k]

Try revving it out of gear at half throttle until you get there. If so, throttle position sensor (which is what Kamin is getting at).

[Oki_R33]

exactly! if your running a stock ECU....

[Cjmartz2k]

Even an aftermarket ECU, wouldn't matter. A jacked up TPS will do the same thing.

Takahara?? I live just behind Met's just up the hill from Takahara Kita! Weird.

[Thanielson]

the tps would make sense cus i got a code 46 nissan that i could find doesnt have a code 46 but inf does it is secondary tps. while driveing to work today i noticed that it only does it at wot.

[skierdude494]

i had a similar problem turned out to be a bad fuel pump switched it with a walbro 255 gained 100 horse power right off the back i dont know just a thought!

[s13_240_rb20]

ok so here id in full detail what is going on. At 5k rpm give or take a few hundred rpms no matter what gear im in the injectors go from arond 70% to 3% basicly stoping all power to the car. anyone any idea what mite be causeing this i dont have a fpr or gauge hooked up to watch the fuel pressure.

I am having these symptoms, except I DO have a FPR and a Fuel pressure gauge. My fuel pressure is:

- steady at idle.-responding to vacuum (builds fuel pressure when throttle is applied, neutral or driving)-DROPS fuel pressure when I am pressing more than an inch on the gas pedal (usually around 5k)-My datascan software shows that my TPS responds to the gas pedal (so I am asssssssuming that it is good)-I do however, suspect my o2 sensor (or wiring) of being bad, but I haven't connected any dots yet...hmmm.....

But if I slow rev it up that high, it will hold fuel pressure just fine most of the time. I have a new walbro as of 3 days ago that is HARDWIRED at 13.8v, also, so I am sure that my problem is not the pump. I am now considering a partially clogged fuel line and hope it is nothing worse.

I'll keep track of your topic and hopefully one of us can help out the other..

--TJ

[s13_240_rb20]

This is what happens when I push too hard on the gas. It happens in any gear and also in neutral.

This was on my way home from work this morning. I was in second gear, around 30 mph or so. The fuel pressure gauge is on top. Ignore the vac/boost gauge on the bottom. It is still not hooked up because no one has helped me figure out where the stock skyline boost gauge plugged in at, so it is sitting at 0 and remains there.

The video begins with the fuel pressure steady at 37psi, cruising 30mph or so. Although the video quality is crap, you can see that the fuel pressure drops to the high 20's during the FIRST time that i apply HALF of the gas pedal, hence NO acceleration due to lack of fuel? After that the fuel dropping and rising is due to pressing halfway on the gas and letting off completely. Keep in mind that if I apply less gas pedal, the engine needs less gas to accelerate, so that is how I am driving it to work...like a grandma....i've slowly accelerated all the way to 110mph and it help perfect fuel pressure. But if I step on it just a little too much....fuel loss = no power = sad day

click below for video:http://s268.photobucket.com/al...5.flv

--TJ