Okay. So I read this: (strait from the boost faq)
Quote:
Fuel Pressure Regulator
This is a wonder of science right here. Basically, its a vacuum actuated valve. The more vacuum the FPR sees, the less it opens. If you are thinking to yourself... "well that doesn't sound right... at 0 vacuum (wide open throttle) you want more fuel, so you'd want it to open more", then you are just a bit backwards. The fuel pressure regulators job is given away by its name. It DOES NOT regulate how much fuel is in the fuel rail, but how much pressure is in it.
If you want to have a real world example of how you can understand this, get a drinking straw. Put one end in your mouth and put your fingers at the end so you can pinch the end closed. Now blow into the straw, but don't pinch the end, thats how the fuel pressure regulator is when there is full vacuum. You don't need a lot of fuel pressure going into the injectors because at full vacuum, the engine's throttle plate is fully closed (you are not accelerating).
Now, blow through the straw, but pinch the end shut (or varying degree's of shut), and blow through it. That is how the FPR is at WOT, where there is no vacuum. It increases the fuel pressure so each time the injectors open, more fuel is forced through them.
I noticed this was true on a friends 2.2 ohv when we hooked up his vac gauge. First I thought it should read from 0 + so I hooked it up in front of the TB and even at WOT it wouldn't register on the gauge. So we hooked it to the FPR line (after pulling it off to varify that it had strong vacuum) It reads like 25 lbs of vac at idle, and drops to zero at WOT. Like it should. On the 2.2 ohv that FPR line is hooked into the intake manifold; in back of the TB... Like it should be!
And then I got to thinking, The ecotec is actually hooked up backwards. It connects in front of the throttle body.... I could see how this may work with stock intakes, but when you put on an aftermarket or custom intake, your going to reduce the amount of sucktion because there is less restriction. Therefore it would have no real vacuum at all. Right?... Experment time!!!
So I looked on the intake manifold and right below the TB on the right, there are 2 little rubber caps on the IM. I pulled one off and attached a vacuum hose from it to the FPR, like it was on the 2.2 ohv. I used the cap to cap off the hole in the intake where the FPR used to connect. I started it up and it purred nice and smooth, and had a bit of a lower, but smoother idle. No lights or bad signs, so I took it up the road and it seemed to have better throttle responce down low, and it wouldn't hesitate at all from an idle.. I didn't get it above 3500 cause the roads are slick today. But It seemed alot pepier. even in 5th. I can't wait once the roads clear to see how it is up high, like 4000+...
I think it helped the car alot. I don't know if I did somthing I shouldn't have so if I did, let me know. But as of right now its going very good. Give it a try, it takes 5 minuets to do / undo. But let me know how it is in the higher rpm's, it looks like it'll be snowing awhile here.
My Sunfire
g/fs eco cav has been like that since i put a intake on it
I should add that I have an 04 Ecotec. I know the the fuel system is different on some 02's... I don't know how this would work on them, I haven't had any expeirence with them. so try at your own risk!
My Sunfire
[quote=97cavie24ls(JDM&00s/c sedans™)]g/fs eco cav has been like that since i put a intake on it
Well I have never heard of it. I used to have a 2.4 but I can't remember how it was setup. Wonder if it's the same?
My Sunfire
5secondrule wrote:I should add that I have an 04 Ecotec. I know the the fuel system is different on some 02's... I don't know how this would work on them, I haven't had any expeirence with them. so try at your own risk!
Actually it's different on all the 02 ECOTECs, not just some.
www.kronosperformance.com / 732-742-8837
Can anyone give a pic of this for the 2200 on how to do it? I would like to try this out on my car and see what kind of difference there is with it!
2009 Ford Mustang V6
the vacuum line to the fpr is the same
the eco is the only 1 that had the line to the fpr on the filter side of the tb
the 2.4 and the ohv were both on the motor side of the tb
I've had a tech II hooked up with a fuel pressure gauge on the rail.
The computer just changes the pulse width of the injector. So there is no difference except lower fuel pressure at idle (with increased injector width pulses)
i've had mine like this since the first intake i had on the car (ebay 2.4 intake in 03) and then my aem...
I've had mine like that since 2002
its the same idea for 2002+
"Growing old is mandatory. Growing up? Definitely optional."
I tried it and I dont think it made my eco run better at all, i think it ran worse
does anyone have any pics of how it hooks up on the eco? just wondering if anyone had a pic? thanks guys!
are you talking about just removing that really really small vacuum line that hooks into the stock '03 eco intake? If so, when I put my RDfabs intake on there was only an inlet for the bigger one- no inlet for that little vacuum line so I just took it off anyway.
sorry man, but you accomplished nothing by doing that.... you may perceive a change but its just the butt-dyno playing tricks on you.
the 04 plus ecotec ecu wants 14.7:1 a/f ratio AT ALL TIMES, and will pull/add pulsewidth to achieve it. Now, a normal oem FPR works by providing a set fuel pressure at atmospheric pressure, which is what the manifold pressure is at wot. As the throttle closes, vacuum increases with the throttle plate angle. As vacuum increases, fuel pressure will decrease (naturally you don't need as much fuel at idle as you do at WOT).
So by changing the vacuum source to the regulator, you basically lowered the fuel pressure at idle (by allowing it to see the true manifold vacuum), but did not effect it whatsoever at wot (it was already seeing atmospheric pressure).... all this means is that at idle your ecu is now adding injector pulsewidth to get more fuel at idle and part throttle to compensate for the lowered idle and part throttle fuel pressures(since before it was only seeing atmo. pressure at all times) and making no changes at wot, since the vacuum/pressure at the regulator is the same at wot as it was before you rerouted the vacuum..
Arrival Blue 04 LS Sport
Eco
Turbo
Megasquirt
'Nuff said
Soon as I installed my AEM cold-air I did this.
FYI, hightempsilicone.com sells vacuum lines in multiple colors. I had the stock plastic one all twisted around, the silicone line looks much better.
-Chris
Not related but I just need to say it...
I Installed my new intake manifold over the weekend!
Power Curve
Been a wile since I've seen an Ope. I didn't know they used an ECOtec in the speedsters.
Some times the best way to get that tailgater off your but is to light a fart.
Nice Opel havent seen one in posted here in a while. does it have any other mods?
Juice pushrods wrote:Nice Opel havent seen one in posted here in a while. does it have any other mods?
I also have a full Milltek SS Performance Exhaust System, a Komo-Tec Induction System, a SuperChips Remap, an Apexi SAFC-2 installed and a Innovate LM-1 + Wideband O2 Sensor and logging kit.
Power Curve
wish we could get opels in the US
Best we're getting now is the Sky (front engine version of the vauxhall 220)
-Chris
I am afraid that I will have to agree with 5secondrule.
I also noticed a difference when I switched the line. A little more torque than normal. When I switched it back. It just was not the same anymore.
I will be installing a vacuum switch to change back and forth from each one. Because I did notice a loss of fuel economy when the mod was done.
New Picture comming this summer.
Ok everyone I got the results that will either make or break this theory. So I decided to get my laptop involved and here is what I got.
Stock Fuel Trim Modified Fuel Trim
Engine Idle 3% 2%
1500RPM 8% 11%
2000RPM 8% 15%
3000RPM 2% 10%
Just keep in mind, no matter what I did the air fuel mixture stayed the same @ 14.6:1 That is just a tenth from the magical 14.7
Like I mentioned before, I also have my line going to the manifold. I managed to pickup a EGR vacuum switch from an older saturn. I will be using the switch to switch between the manifold and air intake. Power or Fuel Anyone?
New Picture comming this summer.
oops, my table did not come out right. Here is another:
---stock-Mod
idle 3% 2%
1.5k 8% 11%
2.0k 8% 15%
3.0k 2% 10%
New Picture comming this summer.
