simevo

iTrader: (1)

I have the Greddy electronic gauge hooked up to the FPR line coming from the intake manifold and works just fine.
You should always see vacuum no matter what the temp is. Only time you won't see vacuum is when you boost or accelerate.
Even when you cruise, you'll be in vacuum unless the engine has some load on it, going up hills and acceleration.

MagEvoVII

Got the BF. that happens to me to cold or warmed up. stuck at 0 boosts up from there then drops to normal after a block or 2. was told it was normal though not sure of cause.

M3lachsilber

Since I mod the forum, did you post in How To's Questions area?

Or search?

You may get some good help there..

jcnel_evo8

iTrader: (2)

Question ... if the FPR is 'held' to keep a higher pressure in the fuel rail, does the computer get a 'fuel pressure' reading from a sensor somewhere, to try to compensate so that the EVO doesn't run 'richer' under a higher fuel pressure?

Thanks,

jcnel.

The Emperor

iTrader: (1)

this is where i connect it..

4ce fed

iTrader: (11)

Wrong place. That is after the FPS. Needs to be before.

The Emperor

iTrader: (1)

soo which hose is the right one where i need to connect the T connectors to..

http://www.jonesland.com/evo/BoostGauge_Install.htm

4ce fed

iTrader: (11)

See the oil dip stick in the pic you posted above? There is a solenoid right behind it in the pic. It is black on a gold bracket bolted to the intake manifold. The vacuum line you tapped into goes to that solenoid. That is the fuel pressure solenoid. On the fuel pressure solenoid, there is another vacuum line going straight to the intake manifold. You can see it in the pic you posted. It is still wrapped in that black coil wrap stuff. That's the vacuum line it should be tapped into.

The link you posted above also tapped into the wrong line.

jcnel_evo8

iTrader: (2)

kewl...any answer to the question posted above?

I don't want to 'hijack' but this seemed to be the best place to ask it.

Quote:

"Question ... if the FPR is 'held' to keep a higher pressure in the fuel rail, does the computer get a 'fuel pressure' reading from a sensor somewhere, to try to compensate so that the EVO doesn't run 'richer' under a higher fuel pressure?

Thanks,

jcnel."

Thanks,

jcnel.

4ce fed

iTrader: (11)

I assume that the ECU will control the fuel accordingly. When a car starts cold, it runs in open loop mode until the O2 sensor is warmed up to the correct temp. On a hot start, when the ECU has the FPS closed, the car should be running in closed loop, since it is already warmed up. Closed loop operation tries to maintain a 14.7:1 AF ratio.

The Emperor

iTrader: (1)

alright..its fixed thanks your guys!

jcnel_evo8

iTrader: (2)

Thanks ... its my understanding that 'some' FI control systems monitor output voltage, and make some assumptions on fuel pump, pumping rates, and try to adjust accordingly. Others actually have a pressure sensor located in the fuel rail that senses fuel pressure and adjusts accordingly.

I'm quite certain (after picking apart the tech. manual again) that the EVO doesn't have a fuel pressure sensor in the rail, but that doesn't mean it can't take a battery voltage reading and try to 'add' a bit more fuel if the battery voltage 'drops' a bit.

Thanks for the responses tho...

and...I'm glad things got fixed.

Cheers,

jcnel.

4ce fed

iTrader: (11)

Not sure about the battery voltage thing. Our cars (like most) use the first O2 sensor reading (by varying the voltage across the sensor) to determine how much fuel to add during closed loop. If the pressure is up, and more fuel is getting added due to the pressure, the ECU will change the pulse width of the injectors to bring the amount of fuel injected down to hit that 14.7:1 ratio.

You are correct, though. Our cars do not have a fuel pressure sensor in the rail.

ReaverEVO

iTrader: (1)

lol.....you basically had him move his line for no reason since theres no sensor...so whos the one who as you said and i quote" Man, you have no idea what you are talking about......The FPR line happens to be the easiest. But, there is a solenoid (FPS) also on that line. " SO WHOS THE ONE WHOS PROVEN THEY HAVE NO IDEA WHAT THEIR TALKING ABOUT????? ........Maybe you should just read the forums since you really have no experience workin on cars!!(que 4ce fed's lying rants of all the high performance cars hes worked on)

Corey

iTrader: (10)

for some odd reason my boost gauge sits at 2 psi when the car is off. Would that mean my gauge is iff by 2 psi? I talked Adam at Z1 and he told me to check all the lines for kinks. I did and I didn't find any.