Hi there, I just had something adjusted in my car by a friend, and it's something I want to run it by some jbo members.
I am pretty ignorant when it comes to engine tuning, so please correct me if I'm wrong.
Apparently, I've got two fuel lines going into the engine. One goes to the fuel rail where the fuel is distributed, and the other is an "out" line where excess fuel that is not used is directed back to a reservoir. (please correct me on this, a tech told me that).
So what my friend did was he somehow managed to block off my "out" line using some hand tools, so that ALL the fuel is being dumped into the engine rather than having some go back into the reservoir. Also, he said that by combining with some adjustments to my tranny (changing gear ratios from the outside?) as well as getting me to use high mileage engine oil, I can gain some power.
This dude is one mysterious guy, and I have a feeling that he isn't always up front with me about these particular adjustments. What I'm wondering is, what the hell did he do to my car? Is it even possible to change gear ratios from the hood. Can he block off a fuel line?
So far, I've had no check engine light and the car is running fine. The car did sound different after he was done. Whether or not I've gained in power, I don't know. I never had my car dyno'ed before or after. I've driven the car across the continent and it's running as smooth as ever.
By the way, my IAT is right where it's supposed to be. I've checked all my wires going into the TB, and I don't think they've been touched or modded.
dont ever take your car back to this guy.
you have in hole and an out hole on your body also. plug up your arse and see what happens.
there are cars that have a "no return" system, but they use varying voltage to the fuel pump to control the fuel. you have nothing to control the fuel pressure.
that "extra" fuel that is supposed to go back to the "resevoir" (which normal people call a gas tank) is NOT getting dumped into your motor. you are getting more fuel because your fuel pressure is rediculously high now which will result in something failing.....like the pump, injectors, or the fpr.
you also cannot change gear ratios from the outside. this man is an idiot
this guy is not your friend.
So is he going to do the labor and $250 to replace your fuel pump too?
That guy is an idiot, you need to put it back the way it was. Dumping more fuel without the air to back it up will only do damage to your engine, not increase power.
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look for a crimped fuel line. and high mileage oil? its just regular oil, maybe a little brake fluid in it to swell your seals. congratulations, you let an complete moron work on your car.
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Wow. The fuel pressure regulator (FPR) works by opening however much is necessary to allow some fuel to go through the return line in order to regulate the pressure in the rail.
Now you have no pressure regulation. Bad.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
"Wow. The fuel pressure regulator (FPR) works by opening however much is necessary to allow some fuel to go through the return line in order to regulate the pressure in the rail.
Now you have no pressure regulation. Bad."
He said there are degrees to which you can do this. So he is tinkering with my FPR, what if LESS fuel is going through my return line? Do I still have pressure regulation then?
And also, for the rest of people who responded. If it's as serious as you say it is, won't my engine light come on? So far, nothing. Car is still running smooth (but it sounds like a more rich mixture than before).
so after everyone said its bad, your gonna wait for a check engine light????
theres a reason its called a "dummy light"
there is no "tinkering" with your fpr. period. the concept of limiting the amount of fuel returning to the tank to raise fuel pressure is correct, but to do that you need an adjustable fpr. you do not have one, so there is no way to change the fuel pressure without crimping a fuel line.
you also cannot hear a rich mixture. thats the sound of your car screaming for help.
oh.....and if he crimped your hard line, you'll be spending a few dollars on a new one.
There is no sensor for fuel pressure, there is no sensor for "hey dumb-@!#$, your pump is about to burn out", there is no sensor for "I'm not getting any fuel through the return line", etc, so no, you won't get a check engine light until its too late.
You're ECU is working hard to regulate the fuel going in, your fuel trims are probably maxed out negative.
Let me put it this way...
YOU ARE DOING DAMAGE TO YOUR VEHICLE, YOU NEED TO PUT IT BACK AS SOON AS POSSIBLE. NEVER BRING IT TO THIS "FRIEND" AGAIN.
And yes, if he crimped the hard line, be prepared to spend well over $200 for new fuel lines, what a nice friend you have, $200 for fuel lines, $250 for a pump, $800 for labor to fix all the stupid crap he's doing to your car, and a dealership or shop that's going to have a good laugh when you bring your car in...
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Big Benny wrote:
He said there are degrees to which you can do this. So he is tinkering with my FPR, what if LESS fuel is going through my return line? Do I still have pressure regulation then?
And also, for the rest of people who responded. If it's as serious as you say it is, won't my engine light come on? So far, nothing. Car is still running smooth (but it sounds like a more rich mixture than before).
The amount of fuel going through the return line has no effect on anything.
Any fuel going through the return line is simply fuel your engine did not need/could not use.
Blocking or restricting the line only increases fuel pressure at the injectors.
Blocking the line results in the fuel pressure just being the maximum the pump can push. This is about 70psi for most GM pumps and drops as the pump wears out.
Restricting the line only results in higher pressure at low fuel demand conditions where more fuel is returned to the tank like at idle. At full throttle it has little to know effect.
Raising the fuel pressure causes more fuel to be injected without the PCM knowing its doing so. Unless you've made airflow changes to your engine (cams, exhaust, intake, heads, blower, turbo) you don't need any additional fuel.
About the trans comment,
there is absolutely nothing you can change on the "outside" of a manual trans that will give you more power.
"Outside" meaning that its something that can be changed without removing the trans and totally disassembling it.
There are only 2 things on the outside (depending on trans) that could be altered: the shifter and 5th gear (isuzu trans only).
Changing either in any way will not change power output.
Changing 5th can only change fuel economy.
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BTW, let me see if I can explain something to you so you know how much of an idiot your "friend" is...
You remember grade school, when they brought out the fire triangle? You need 3 things for a fire:
1. Heat
2. Oxygen
3. Fuel
Now the heat ignites the oxygen and fuel, that's given, but adding more of oxygen without adding more fuel does NOT make more power. Adding more fuel without adding more oxygen does NOT make more power. There is a delicate balance there. Your car (ECU) takes care to a point (which will even cover non-stock items such as intakes and exhausts) to add more fuel when it detects more air has been added in. It also adds more fuel to richen up the mixture to the RICHEST YOU WANT TO BE to make the best power (or close enough to it from the factory) that your engine can make. This is called "Power Enrich" mode and its built into the ECU.
Why do you think that when they fight oil field fires, they use explosives to
put out the fire, because adding more fuel to the same amount of oxygen will douse or put out the flame. Now in a car, too much fuel actually washes the oil coating on your cylinders off as your pistons move up and down, causing a lot of premature wear on your parts. Your fuel pump is not meant to run at pressures any higher than stock, so putting ANY restriction on it is going to cause it to burn out (hell, clogged fuel filters cause it).
Now, go fix your car and chalk it up to a lesson learned. But do it now before more damage turns into more money.
4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!
wow.
thats all I will say since everything I would have said has already been stated many, many times.
I wonder if this guy just popped the hood... tinkered around with a few things and revved the engine a few times... and then told you he'd worked all this magic so you'll feel he's done something useful.
I mean... pinching a line is one thing, but if he said he changed your gear ratios... well... that shows that either he's just making stuff up out of the blue, or has no idea how to explain what he's really done. That being the case... you repeating it here has just turned into a game of telephone where we now get to hear your interpretation of his piss poor explanations or lies.
If you think he's actually done something, you'll probably want to get a real mechanic to look at it before it costs you big money, and you might want to get him to show the mechanic what he's done.
something doesn't sound rite here. Did you ask him to show you what he done or anything. Anytime in life - Make sure you ask questions and know what is going on exspecially when its yours.
you should hook the return line into the intake and call it nitrous
or
to help us all out hook you cooling line into the black box on the front of the engine where the breather hooks into this will help cool your engine oil by 100%
JBO since July 30, 2001
The last post in this thread was September 5th, 2008. Posting joke answers this late is pretty gay.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
i tought it was funny
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Mike wrote:The auto to manual swap is not as involved as you would think.
Get all the parts you need in a pile, and drive the car into it.
They will find their way into the correct places.
