Hey guys,

I own a stock 2004 350z convertible - quick little back story to before I had this problem.

- the brakes were bad so me and my dad were waiting for a decent day to work on them
- the car sat for almost a week and I started it yesterday and it struggled to start but idled fine

when I went to start it today it struggled but worked nonetheless. I let the car warm up to temp and gave it a quick little rev and thats when it died (I revved it to above 3k rpm). The second start up had the same struggle and then I revved it again to a little above 4k rpm where it died out again. I really don't know what this could be if anyone could help that'd be great.

How long will it idle and not touching the pedal?

The idle is fine, it'll get to temp and drop under 1k but its normal idling nothing drastically low. its just when I rev it a little above 3k it'll begin to drop like it normally would except it would drop all the way down to 0 rpm and just sputter out

could be a failing throttle position sensor, but you would likely get a SES/Check Engine Light and a code for that.

also maybe a dirty fuel filter

Been a bit since I worked on mine but I am thinking that you have enough fuel pressure for idle but increasing the RPM level is creating a demand that either the fuel pump or fuel pressure regulator is not keeping up with. I would go with the dirty fuel filter save for the fact that there is plenty of fuel coming through and cycling back to the fuel tank for a proper idle. I alos don't think it's throttle position sensor because you rev the motor to 3000 or 4000 rpm. If the sensor was bad, I don't think that would happen. I think the next course of action is to check the fuel pressure at the fuel rail supplying the injectors.

chasracer2 wrote: ↑

Sat Dec 01, 2018 6:26 pm

Been a bit since I worked on mine but I am thinking that you have enough fuel pressure for idle but increasing the RPM level is creating a demand that either the fuel pump or fuel pressure regulator is not keeping up with. I would go with the dirty fuel filter save for the fact that there is plenty of fuel coming through and cycling back to the fuel tank for a proper idle. I alos don't think it's throttle position sensor because you rev the motor to 3000 or 4000 rpm. If the sensor was bad, I don't think that would happen. I think the next course of action is to check the fuel pressure at the fuel rail supplying the injectors.

Thanks man I will check it and then let you guys know if that was it

Update 9 days now, I think my brake booster is failing bc when I brake there is a grind then an electronic sounding whine. Idk what that is. The front pads and rotors were replaced and the rears were fine. The revving and idle has been weird, so when it gets to temp the idle will drop to below 600 rpm and it'll get a little shakey and some knocking noises will occur. If anyone has any clue to this pls lmk. thanks!