Cheapest ECU bypass...

[mr.niceguy]

There are many ways to mod the ECU. But if you cant, you can install a AFPR(adjustable Fuel pressure Regulator) Stock setting is usually 43psi. If you cant get the ECU to reduce fuel input. Cut the fuel supply manually by reducing the incoming fuel pressure. IE lower to 35psi. YOu can get 1 on EBay for $20.

Hows it work? An FPR acts as a constrictor on the return line to your fuel tank. aka like a thumb on the end of a garden hose. higher FP= more fuel better performance, (12.5 AFR) is peak performance. Lower FP = better mpg. DONT go 2 lean though.

This should only be done w/ an AFR(air to fuel ration gauge) and a EGT(Exhaust gas temp) gauge is also a good idea Anything above 1600F and you will be in trouble... eventually sooner or later. 15-15.5 AFR reading is slightly lean but ok anything higher and youll risk damage like melting your cat if you have 1 or warping valves ect.

Now if you wanted to just use an AFPR to enhance your mpg you can. But just remember since the HHO gives more O reading to the O2 sensor I would add 0.4-0.6 to AFR gauge to get an accurate reading.( If you have a higher LPM based on your engine size you could add more, but the rule of thumb is .5L HHO/ 1Lengine) The ECU shoots for 14.7 AFR (stoich) but really this same gas ratio should be about 15.2 w/ HHO. So simply reduce your Fuel pressure until you reach this reading. This setup will cause a check engine light(CEL), but the good thing about it is that the ECU wont be able to add anymore fuel once put in closed loop, just lower the FP till the readings are as state above, about 15.2 and you should be fine.
Check the spark plugs after a week or 2 and make sure they are not white. White indicates a lean cond. Tan is the proper color.

NOTE: only adjust the FP when the car has fully warmed up. It will run richer when the car is warming up. This is not a bad thing.
If youre worried about passing an inspection. Just raise FP back up erase CEL, pass, then turn back down.

edit 11/27: well so far from my results the ECU has just bumped up the injector duty cycle a little bit with the lower fuel pressure resulting in NO MPG gain. Coulda swore that would have worked, just ignore this thread, the ECU is smarter than my idea

[myoldyourgold]

Mr. Nice guy have you done this and had results? Can you give us the particulars? Are you saying that the system will stay in open loop with the check engine light on all the time? What would happen if something else goes wrong and the check engine light is already on so you would not know it? Interesting cheap idea.......

[mr.niceguy]

Yes I have done this but with a completely different setup for a turbo application w/ bigger injectors and an FMU. Ill spare the details.

Basically when you drop the FP the ECU will realize its not getting enough fuel and go into edit: open loop NOT closed loop. This will cause the ECU to go to preset maps based on other sensors. Closed loop is "safety" mode and injects extra fuel. Simply just turn down the fuel pressure till it gets back to optimum AFR's and your good.

Youre right about the down side. The CEL would be on all the time, but that really doesnt bother me. I have a scanner and check my codes 1x/ month along w/ all my other fluids. You can check it more if youd like, but really the CEL is worthless. I believe its just for the OBDII sensors. I have all the info I need on my dash oil pressure battery voltage ect.

[Quebecker]

Yes I have done this but with a completely different setup for a turbo application w/ bigger injectors and an FMU. Ill spare the details.

Basically when you drop the FP the ECU will realize its not getting enough fuel and go into closed loop. This will cause the ECU to go to preset maps based on other sensors. Closed loop is "safety" mode and injects extra fuel. Simply just turn down the fuel pressure till it gets back to optimum AFR's and your good.

Youre right about the down side. The CEL would be on all the time, but that really doesnt bother me. I have a scanner and check my codes 1x/ month along w/ all my other fluids. You can check it more if youd like, but really the CEL is worthless. I believe its just for the OBDII sensors. I have all the info I need on my dash oil pressure battery voltage ect.

I think you make a small mistake. You need to talk to OPEN LOOP MODE
Basically when you drop the FP the ECU will realize its not getting enough fuel and go into open loop.

Regards

[Weapon_R]

I think you make a small mistake. You need to talk to OPEN LOOP MODE
Basically when you drop the FP the ECU will realize its not getting enough fuel and go into open loop.

Regards

You are correct Quebecker. This must also be done in open loop. So again the O2 sensors should be unplugged.

[mr.niceguy]

I think you make a small mistake. You need to talk to OPEN LOOP MODE
Basically when you drop the FP the ECU will realize its not getting enough fuel and go into open loop.

Regards

Woops you are right, I always get the 2 confused because to me open loop would seem like the ECU would be open to sensor readings, but its just the opposite. I edited the previous post.

You are correct Quebecker. This must also be done in open loop. So again the O2 sensors should be unplugged.

I would leave the O2 sensor plugged so I can get a proper AFR reading to my aftermarket gauge, unless you have one that provides its own o2 sensor like a Innovative LC-1. The ECU stays in Open Loop until the CEL is cleared. The ECU uses maps based off the TPS and coolant sensor and dis-regards the O2 reading.(at least in my car 97 probe GT) So its not going to add anymore fuel weather its plugged in or not.

Also would use a digital AFR gauge. Wideband is better, but narrow band will work fine for this purpose.

[koya1893]

There are many ways to mod the ECU. But if you cant, you can install a AFPR(adjustable Fuel pressure Regulator) Stock setting is usually 43psi. If you cant get the ECU to reduce fuel input. Cut the fuel supply manually by reducing the incoming fuel pressure. IE lower to 35psi. YOu can get 1 on EBay for $20.

Hows it work? An FPR acts as a constrictor on the return line to your fuel tank. aka like a thumb on the end of a garden hose. higher FP= more fuel better performance, (12.5 AFR) is peak performance. Lower FP = better mpg. DONT go 2 lean though.

This should only be done w/ an AFR(air to fuel ration gauge) and a EGT(Exhaust gas temp) gauge is also a good idea Anything above 1600F and you will be in trouble... eventually sooner or later. 15-15.5 AFR reading is slightly lean but ok anything higher and youll risk damage like melting your cat if you have 1 or warping valves ect.

Now if you wanted to just use an AFPR to enhance your mpg you can. But just remember since the HHO gives more O reading to the O2 sensor I would add 0.4-0.6 to AFR gauge to get an accurate reading.( If you have a higher LPM based on your engine size you could add more, but the rule of thumb is .5L HHO/ 1Lengine) The ECU shoots for 14.7 AFR (stoich) but really this same gas ratio should be about 15.2 w/ HHO. So simply reduce your Fuel pressure until you reach this reading. This setup will cause a check engine light(CEL), but the good thing about it is that the ECU wont be able to add anymore fuel once put in closed loop, just lower the FP till the readings are as state above, about 15.2 and you should be fine.
Check the spark plugs after a week or 2 and make sure they are not white. White indicates a lean cond. Tan is the proper color.

NOTE: only adjust the FP when the car has fully warmed up. It will run richer when the car is warming up. This is not a bad thing.
If youre worried about passing an inspection. Just raise FP back up erase CEL, pass, then turn back down.

Mr. Niceguy,
I've been away from the forum due isolated work. One thing I picked up from the long post above, is "Now if you wanted to just use an AFPR to enhance your mpg you can. But just remember since the HHO gives more O reading to the O2 sensor I would add 0.4-0.6 to AFR gauge to get an accurate reading". It is stating that using HHO will give you more O reading to the O2 sensors. I disagree with you there, the reason the O2 will tell the ECU to schedule more fuel is because using HHO promotes clean and efficient burn, hence you are eleminating emission in turn you have a cleaner exhaust the O2detects not from the MINUTE amount of Oxygen from your system. It is so minute that you probably cannot measure it, and if it was a large amount, one would think, again I am not the expert in this field. That amount would be used during combustion process.

I've performed test on my vehicles and clients, what we are trying to do is outside the box, the ECU will only learn what is close to the norm operation. hence I've taken the another approach to saving on vehicle that will not respond. that's increasing the power to weight ration, I discovered this by accident with the Infinity I was working with.

At first I was told it had two O2, one front and one rear. I treated the front like I did others decrease the signal by 100mv initially and increase the rear by 200mv. I discovered later that it has more than two O2, it had four. two front (narrow) and two rear. My initial setting thinking there are two o2, I increased the signal on one and decrease on the other. when I discovered the other two O2 I re-wired everything as per the EFIE instruction, increase the signal on the rear 200mv and decrease the front by 100mv to 350mv. The mileage went down, I was puzzled for sometime. then it hit me, the fron setting I changed to add to the signal and maintain the standard signal on the rear. It is consitantly yielding 29.2 mpg city using regular gas vice the high octane recommended.

With those setting I can credit it to the power to weight ration increase. I have other example but those I cannot share as they are being patended with the application...

[Quebecker]

Hi Ben,

I have some difficulty understanding. Would it be possible to answer my questions because I'd like to make these settings to my car seems not to like with the addition of HHO gas :-(


Your front sensors are Wideband sensor (A/F ratio sensor) or Narrow (conventional O2 sensor) ?


Initials setting
===========
Front: -100 mV
Rear: +200 mV


Final setting ???
============

Front: -350 mV (from -100 to 350)
Rear: +400 mV ffrom 200 to 400)


Regards

Rémi

[koya1893]

Hi Ben,

I have some difficulty understanding. Would it be possible to answer my questions because I'd like to make these settings to my car seems not to like with the addition of HHO gas :-(


Your front sensors are Wideband sensor (A/F ratio sensor) or Narrow (conventional O2 sensor) ?


Initials setting
===========
Front: -100 mV
Rear: +200 mV


Final setting ???
============

Front: -350 mV (from -100 to 350)
Rear: +400 mV ffrom 200 to 400)


Regards

Rémi

Maybe I did not express that correctly:

This is for narrow band O2.

front = 400mv At this setting you are decreasing the standard signal from 450mv down to 400, less 50mv.

rear = 20mv At this setting you are only adding 20 mv to the standard of 450mv to signal the ECU.

At this setting re-set your ECU several times withint 300 miles, so every 100 miles re-set, then run it like this for 500miles. The other thing I discovered on the Infinity is inducing close 1 to 1 ratio. I was inducing 2-2.5LPM.

[Quebecker]

Maybe I did not express that correctly:

This is for narrow band O2.

front = 400mv At this setting you are decreasing the standard signal from 450mv down to 400, less 50mv.

rear = 20mv At this setting you are only adding 20 mv to the standard of 450mv to signal the ECU.

At this setting re-set your ECU several times withint 300 miles, so every 100 miles re-set, then run it like this for 500miles. The other thing I discovered on the Infinity is inducing close 1 to 1 ratio. I was inducing 2-2.5LPM.

Ben,

I'm not 100% sure but I think for the front O2 sensor, the EFIE don't decreasing 400 mV but it increase by 400 mv. Because it's a narrow band O2 (conventional O2).

An narrow band O2 sensor, no matter whether forward or backward works the same way.


Narrow band O2 sensor -> 0 to 1 volts
===========================

0.05 to 0.4 v, lean mixture
0.45 v, stoic
0.5 to 0.95 v, rich mixture

--> The EFIE must increase the voltage


Wideband A/F ratio sensor -> 0 to 5 volts
=============================

3.3 v and less (current flow - ): rich mixture
3.3 v (no current flow): stoic (14.7:1 ratio)
3.3 v (current flow +) : lean mixture

--> The EFIE must decrease the voltage

Correct me if I am wrong

Regards
Remi