cessblood

I think it's the the fuel pressure system that cause this problem. I'm not the only one who thinks it's the fuel pressure. My friend had this problem since feb of this year.

dgHotLava

the real culprit is the pressure regulator disc in the fuel canister/pump.
it is responsable for keeping the pressure in the line when the car is shut off.

amdforever

So if this is the problem, do you think a new fuel pump would fix it? If so shouldn't Toyota/Scion be sending out a recall to fix these things. If I'm not mistaken I was under the impression that the fuel system depressurized anyway when the car is turned off.

dgHotLava

the fuel pump is not the problem...
the pressure regulator disc is...it is not part of the pump but rather an inside part to the canister the pump is in...(along with the level float sensor)

the only way for scion to start recalling(tsb'ing this) is to first know for certain what the issue is, and then find a 100% remedy.

the only way i know this is my issue...
i replaced the fuel rail and have a fuel pressure gauge.
i'll park the car and show 40psi.
when i leave it for several hours..it will drop to 30...20...15...
then i'll start the car (or try to crank the motor) and i'll see the pressure come back up...

now, what is supposed to keep the fuel pressure (on our single line deliver systems) is a regulator disc in the fuel tank pump canister. somewhere between the fuel line and the fuel pump. it will not allow more pressure than xx amount into the fuel line...and will act like a check valve when the pressure is less from the pump than in the fuel line.

i've done it three times, each time lasts for several months.
i still have not figured out what the cause is to make it fail (and this is why scion has not issued a TSB.

amdforever

WOW You are by far the most knowledgable poster on that I have seen so far Thanks for explaining that because not all of us were getting what you were talking about without backing it up. Now they just need to get on the ball and fix it. Although its not too much of a problem, more of an annoyance for most people. But seriously, thank you for explaining what you have done and how you could prove it, its appreciated.

KiKaZ-tC

iTrader: (1)

i'm not sure, truthfully i doubt turning the ignition to "ON' does nothing, i was told not to keep it there for no longer than say... 5 seconds because your fuel lines should be pressurized by then, i believe it does turn on the fuel pump. Only thing i can see happen if you leave your ignition in the 'ON' position all night is you won't be able to start your car because your battery will be dead.

amdforever

Um...if you read her last post she said she had a fuel pressure gauge. I'm sure that she would know whether or not the fuel pump turned on IE, the key would be in the on position and the pressure on her gauge not climbing.

jkuz99

Ive had my s/c on for a few weeks and only this passed week has it started to bog when starting in the morning. it still starts first time but now i experience a bog when doing so.

KiKaZ-tC

iTrader: (1)

im not here to argue, just trying to express my opinion and give suggestions as to what has been working for me.

dgHotLava

yes, the older cars would pump gas as soon as you turned the key to on...it would also power up the ignition systems.
this led to some cars burning out the ingnition systems prematurely.

i do belive it is wise to wait a few seconds (1-2) between each key position.
this gives you time to observe the car for any problems.


when i did the fuel rail and pressure guage, i pinched an o-ring on two incetors...
i thought since i turned the key to on and they did not leak...i was fine...
but once i cranked the motor it was like a fountain...lol

cessblood

I wish someone could get a video clip of this problem but it's kind of hard to get a video since this problem happen randomly.