emfc_22

been working on a little project for a while now and have ran into a snag. i have messed around w/ the fuel rail now and have learned how to increase rail pressure w/radio shack parts. now i can load up a circuit until the motor runs rough and the pump rattles like crazy then back it down and get a smooth idle. with the smooth idle it runs really smooth and you can feel the power gain ok w/a little smoke on take off, even a little rolling smoke when you get into it. but when i load the ciruit more and get the rough idle i get a very dark heavy cloud and a very strong acceleration till it cuts in out running rough then i turn it back down fast hoping nothing is broke. i was just wandering if someone would know what would make it run so rough and cut in out because i like the power at that point. i have advanced my timeing useing info from past posts hoping to end the problem but it hasn't. maybe it is an injector issue with too much pressure or maybe rail pressure running low? don't have a clue

mikmaze

presure is one thing, but it does lead to a nead, for flow......... I bet an upgrade to the supply side of the system would smothe it out, would it break something? probably/////////

emfc_22

Surely I Am Not The Only One Cutting Wires Trying Thing For Myself Someone Has Had To Of Tryed This And Know What I Am Talking About

TAS05CTD610

There was one other guy on here a long time ago cutting wires to the injecters this and that. He got a bad rap for doing all this with no pictures, dyno results, and a lot of issues. Building your own box is one thing, but take into consideration that when these chip builders build a box they have tons of money and research as well as a whole bunch of tools we don't have. That's why it costs so much to buy them. I would worry about building my own unless you have a scope, and a whole boat load of computer electronics to see what your truck is doing. Then you could watch your pressure in the rail, watch timing, everything. Everything MUST work together or something will go boom

MikeyB

You need to get a rail pressure gauge to see what's going on. PM 'doug' here on this forum about his new gauge.
Most likely the rail pressure relief valve is opening due to the extremely high pressure. It's about a $400 part if damaged or weak.

MikeyB

Dodgezilla

All that pressure is gonna kill your injectors.......

4x4not

Just messing around with wires and simple Radioshack chips is a lot different than ENGINEERING a solution. There is a reason 99.999% of people don't start hacking into their wiring harness. Heck, I'm an Electrical Engineer and I wouldn't even consider it unless I had the (expensive) equipment to record and detect what was going on.

acook

thinks ill just pay for the programmer/box itll be cheaper then replacing a mess of broken parts

TAS05CTD610

Messing around with wires on a brand new 40K truck!!!! . That's like if your wife caught you with another woman and you told her "oh it was only once" yeah right. But yes that's why so many people buy a chip from a company. You ever read there warrentie. Sure there not responsible for damage to your truck that you inflict, however have spend hundreds of thousands (possibly millions) of dollars on a product that has been researched, and tested. Lots of reasons not to just try something. Tools cost money (and hey if you have them go for it) but there's a lot to do and look for when you build a chip. Any good chip builder will tell you about the motors they've trashed building one also. If you've ever built a extreamly good chip or motor, without any issues, you got one comming.

But I'm not a put downer. Deffinatly good luck with the chip. You never know, every chip builder started somewhere. you could be the next new guy

emfc_22

thanks for all the responce so fast i kinda figured i would get the you should know better than cutting things up on a perfectly good truck. but i just can't help but to mess w/things and seeing what happens.

Hey dodgezilla you made the remark about the injectors and i read a classified on tdr of a guy selling 75 hp tips that came from the dealership for 500 bucks ever heard of this?

and i also kind of wondered about the relieve valve releasing but i thought it would just blow not reset but i may be wrong. been wrong before

Leon441

Keep on with what you are doing. The manufacturers of these trucks usually will slip and tell you about a test truck not a slew of them. Although I would think pressure gauges would be a great idea to keep from hurting anything. I don't know if you may hurt your truck toying with it but it's your why not. I am planning to experiment with a lift pump. Guess the aftermarket has a better answer for that too. One that voids warranty and is easily seen.

qzilla

The problem you are facing is that to make enough difference at WOT you are putting a signal out of range for the ECU.

At minimum you need some sort of microcontroller so you can at least provide some logic to what you are doing. You could at least turn your resistor on or off. These trucks are considerably more finiscky than the older trucks.

If you need some help, I will give you some inputs, but the way you are going about it now will not work.

mikmaze

I was wondering when someone would chime in with some expertise, and low and behold, the top wizzard has spoken,. take his advice and his offered help, this man knows what he is doing.

DmaxEter

If your increasing the rail pressure, you may be running the rail out of fuel. Your CP3 is flowing more fuel than your supply pump can supply!! Just a thought. My truck runs the rail dry on the top end with my BD box in the highest setting.

emfc_22

qzilla you know what i am doing then. on the pressure sensor i have a 100 ohm reducer in line w/a 25 ohm adjustible. so at start up i turn off the 25 unit until operating temps are in check. then rotate the 25 on intil i get the before mentioned effect w/the motor, then turn it down slightly until i get a good idle. so i am guesing i am pushing around 106-108 ohms before it starts to act up. i am starting to think the only way to make more power w/the fuel is to adjust the pulse width of the injection but haven't the slightest on how to do that myself. not yet anyway.