Intelligent Fuel Trimmer (made by hameed)

[coolsmart]

Great work, munno be sikha do yar. Am eager to learn, why not u start a short course related to automobile.

[hameeds01]

I appreciate your efforts and do wish you the best of luck.

Let us start by asking the purpose of this device. What problem does it propose to resolve, and how do you plan to achieving the solution?

We can talk about the performance and finally the market for such a device later.

Sir the primary purpose of this device is to optimize the AFR or to provide a freedom to adjust the AFR manually in order to improve mileage. Hopefully it will resolve poor mileage issues. i started it for my friend whose 1NF-FE equipped automatic vehicle gives only 8km/L.

on the other hand it can be used in racing high performance vehicles, this device is intelligent enough to sense the acceleration demand by differentiating the input injector pulses & thn increases the injector width for some extra boost.

[hameeds01]

Great work, munno be sikha do yar. Am eager to learn, why not u start a short course related to automobile.

Hmmm nice idea but dude i hate teaching stuff, man u can come & join me

[VCheng]

Sir the primary purpose of this device is to optimize the AFR or to provide a freedom to adjust the AFR manually in order to improve mileage. Hopefully it will resolve poor mileage issues. i started it for my friend whose 1NF-FE equipped automatic vehicle gives only 8km/L.

on the other hand it can be used in racing high performance vehicles, this device is intelligent enough to sense the acceleration demand by differentiating the input injector pulses & thn increases the injector width for some extra boost.

Manually? If the car has a properly functioning OBD2 system, the ECU will adjust for optimum combustion up to 50 times a second, in both steady state and for acceleration, as well as optimal ignition timing.

If the car has been tampered with and no longer has the stock system, then you might be able to improve matters, but even that is doubtful that manual control will work better than the default limp mode.

[hameeds01]

Manually? If the car has a properly functioning OBD2 system, the ECU will adjust for optimum combustion up to 50 times a second, in both steady state and for acceleration, as well as optimal ignition timing.

If the car has been tampered with and no longer has the stock system, then you might be able to improve matters, but even that is doubtful that manual control will work better than the default limp mode.

Sir what u say about 5 year old WB O2 sensor?? 5year old O2 sensor reading will be same as Zero meter WB O2 sensor???

My device updates itself on every single Engine revolution, if an Engine is running at 1000RPM then it will update @ 16.7Hz.

Sir u know what lots of People r using MAP/MAF enhancer & there r happy with it even though its a wrong way to alter injector width.

My Device has nothing to do with ECU internal maps, it jst modifies the Injector width

Sir can u plz shed some light on the functionality of this particular device ??

CobraUSA | Fuel Management

[Xulfiqar]

In the old civics and even some of the new corollas being made by IMC have a trim pot instead of an 02 sensor. The old Daewoo racer also had that, it was the bit the mechanics fiddled with to trim back fuel (but that car also had a RON switch to account for poor fuel)

This device you are making at most can be used to adjust the fuel to adjust for baromatic pressure difference and fuel quality difference, In general cat equipped cars run a bit rich to ignite the cat to work. The ECU looks at the pre and post cat sensors to keep the cat working (mostly post 02 does this) the pre 02 constantly pulses and sends feedback to the ECU to correct the fuel. if your engine does not utilise a map sensor in conjunction with a MAF sensor it cannot decide what the baro pressure is before startup and also cannot determine engine load on overrun and lugging.

Its a great idea - but it should be done in conjunction with some new parts to sense the exhaust correctly. And before any of this you should first actually see that the exhaust O2 sensors and CAT are working properly.

[hameeds01]

In the old civics and even some of the new corollas being made by IMC have a trim pot instead of an 02 sensor. The old Daewoo racer also had that, it was the bit the mechanics fiddled with to trim back fuel (but that car also had a RON switch to account for poor fuel)

This device you are making at most can be used to adjust the fuel to adjust for baromatic pressure difference and fuel quality difference, In general cat equipped cars run a bit rich to ignite the cat to work. The ECU looks at the pre and post cat sensors to keep the cat working (mostly post 02 does this) the pre 02 constantly pulses and sends feedback to the ECU to correct the fuel. if your engine does not utilise a map sensor in conjunction with a MAF sensor it cannot decide what the baro pressure is before startup and also cannot determine engine load on overrun and lugging.

Its a great idea - but it should be done in conjunction with some new parts to sense the exhaust correctly. And before any of this you should first actually see that the exhaust O2 sensors and CAT are working properly.

@ Xulfiqar

Sir i was waiting for ur precious input thankz u r here

Sir now u tell me is there any worth of my new idea "Intelligent Fuel Trimmer" have u seen any thing like this before?? its like an intermediate ECU that modifies the actual injector width, i know its not a big deal for u to digest its functionality.

The soul purpose of this device is to adjust the fuel for baromatic pressure difference and fuel quality difference specially for JDM vehicles which give poor mileage on local fuel.

this device will provide a freedom to adjust the AFR ratio manually without disturbing the overall stock ECU functionality

[Xulfiqar]

@ Xulfiqar

Sir i was waiting for ur precious input thankz u r here

Sir now u tell me is there any worth of my new idea "Intelligent Fuel Trimmer" have u seen any thing like this before?? its like an intermediate ECU that modifies the actual injector width, i know its not a big deal for u to digest its functionality.

Yes I have seen it - infact a lot of people have - the old SAFC and VAFC were exactly this. Its a good idea but it would be better once you read the ECU for O2 activity on a freshly tuned car with new parts run for about 500 kms. Im saying this because all modern ECUs will send out high signal to the injectors if its sees lean condition and can also cause conflict in the misfire count reading too.

[hameeds01]

@vcheng

Sir i have a simple question 4 u, if OBDII WB O2 sensor runs in such a tight feedback loop then y the performance changes by upgrading free flow intake /Exhaust system?? y fuel quality make difference?
U know what in control systems if O/P is fully dependent on feedback sensor then such variations/disturbance (free flow intake/ exhaust) can’t make any difference because the ECU will recalibrate itself.

Y the fuel consumption changes after removing catalytic converter??
I hav seen people who change OEM injectors with aftermarket high flow rate injectors just for performance/racing.

[VCheng]

Sir what u say about 5 year old WB O2 sensor?? 5year old O2 sensor reading will be same as Zero meter WB O2 sensor???

My device updates itself on every single Engine revolution, if an Engine is running at 1000RPM then it will update @ 16.7Hz.

Sir u know what lots of People r using MAP/MAF enhancer & there r happy with it even though its a wrong way to alter injector width.

My Device has nothing to do with ECU internal maps, it jst modifies the Injector width

Sir can u plz shed some light on the functionality of this particular device ??

CobraUSA | Fuel Management

If any sensor in the OBD2 system is not working properly, the correct solution is to replace or repair it, not add another doohickie. The Cobra device is for motorcycles only that do not have OBD2 compliant systems. That approach does not apply to cars with functioning OBD2 systems.

@VCheng

Sir i have a simple question 4 u, if OBDII WB O2 sensor runs in such a tight feedback loop then y the performance changes by upgrading free flow intake /Exhaust system?? y fuel quality make difference?
U know what in control systems if O/P is fully dependent on feedback sensor then such variations/disturbance (free flow intake/ exhaust) can’t make any difference because the ECU will recalibrate itself.

Y the fuel consumption changes after removing catalytic converter??
I hav seen people who change OEM injectors with aftermarket high flow rate injectors just for performance/racing.

Most of the claims of performance with free flow intakes and exhausts are just that - unproven claims.

Dumping more fuel and air for more power for racing is different, since you will not care about fuel economy or emissions on the race track. But that is not your goal with this device, is it?

[hameeds01]

Yes I have seen it - infact a lot of people have - the old SAFC and VAFC were exactly this. Its a good idea but it would be better once you read the ECU for O2 activity on a freshly tuned car with new parts run for about 500 kms. Im saying this because all modern ECUs will send out high signal to the injectors if its sees lean condition and can also cause conflict in the misfire count reading too.

Sir how u compare 5year old O2 sensor signal with a new O2 sensor reading?? can we rely on it?? as u know with the passage of time the life of O2 sensor doctorates then how it can optimize AFR??

[Xulfiqar]

old O2 sensors get lazy, you need new ones to read correctly.

[hameeds01]

If any sensor in the OBD2 system is not working properly, the correct solution is to replace or repair it, not add another doohickie. The Cobra device is for motorcycles only that do not have OBD2 compliant systems. That approach does not apply to cars with functioning OBD2 systems.
Most of the claims of performance with free flow intakes and exhausts are just that - unproven claims.
Dumping more fuel and air for more power for racing is different, since you will not care about fuel economy or emissions on the race track. But that is not your goal with this device, is it?

Sir mostly ECU never detects a lazy O2 sensor. As we r living in pak where no one knowz that O2 sensor needs to be replaced aftr certain mileage + its not available + too expensive.

[hameeds01]

@ VCheng

Sir if O2 sensor makes that much impact then y ECU EEPROM is loaded with Fuel map??? y it needs to monitor the intake Air flow rate??

in my point of view O2 sensor is there for lil fine tuning

May b i m wrong

[VCheng]

@ VCheng

Sir if O2 sensor makes that much impact then y ECU EEPROM is loaded with Fuel map??? y it needs to monitor the intake Air flow rate??

in my point of view O2 sensor is there for lil fine tuning

May b i m wrong

The fuel map represents only the baseline the starting point, and the O2 sensors help maintain the running fuel trim. The other key sensors are the ambient air temp sensor and the Mass Air Flow meter, among others. There are usually two sensors per catcon, one upstream and one downstream, as well as other ancillary sensors, like knock sensors, cam position sensor etc.

These all work together as a system. Adding an interfering device in modifying the injector profiles is not going to work well.

[hameeds01]

The fuel map represents only the baseline the starting point, and the O2 sensors help maintain the running fuel trim. The other key sensors are the ambient air temp sensor and the Mass Air Flow meter, among others. There are usually two sensors per catcon, one upstream and one downstream, as well as other ancillary sensors, like knock sensors, cam position sensor etc.

These all work together as a system. Adding an interfering device in modifying the injector profiles is not going to work well.

Sir my friend's car mileage is 8KM/L & its 2NZ-FE no Check Engine Light is there. Toyota company checked it via Computer & said the car is perfect but i know its running rich, what if i install this device in my frined's car & set the AFR via meter wil it work??

[VCheng]

Sir my friend's car mileage is 8KM/L & its 2NZ-FE no Check Engine Light is there. Toyota company checked it via Computer & said the car is perfect but i know its running rich, what if i install this device in my frined's car & set the AFR via meter wil it work??

How do you know that the car is running rich?

[hameeds01]

How do you know that the car is running rich?

@vcheng
Because of poor mileage

Sir IA on this weekend i wil do an experiment on my vitz "2SZ-FE" in order to verify my device, first i wil reduce the injector width to lean out AFR then i wil monitor the injector width on oscilloscope if OEM ECU brings back the injector width then my device is useless.

for eg if i reduce the injector width by 25% then the ECU must increase the actual injector width by 25% in order to achieve an optimum AFR.

[Xulfiqar]

@VCheng
Because of poor mileage

Sir IA on this weekend i wil do an experiment on my vitz "2SZ-FE" in order to verify my device, first i wil reduce the injector width to lean out AFR then i wil monitor the injector width on oscilloscope if OEM ECU brings back the injector width then my device is useless.

for eg if i reduce the injector width by 25% then the ECU must increase the actual injector width by 25% in order to achieve an optimum AFR.

to detect lean and rich - you need to view the o2 sensor reading, also look at the short and long term fuel trim to confirm it. You cannot guess the fuel intake by km/lit

[VCheng]

@VCheng
Because of poor mileage

Sir IA on this weekend i wil do an experiment on my vitz "2SZ-FE" in order to verify my device, first i wil reduce the injector width to lean out AFR then i wil monitor the injector width on oscilloscope if OEM ECU brings back the injector width then my device is useless.

for eg if i reduce the injector width by 25% then the ECU must increase the actual injector width by 25% in order to achieve an optimum AFR.

No. Poor mileage can be due to many other causes, not running rich, in the absence of other symptoms. As explained below, you need to view the O2 sensor readings in real time on an OBD2 scanner.

If you vary the injector pulses by as much as 25% you will likely fall outside of the parameters that the ECU is able to adjust for properly. If the engine runs too lean or rich for long periods of time, you will risk ruining the catcon.

to detect lean and rich - you need to view the o2 sensor reading, also look at the short and long term fuel trim to confirm it. You cannot guess the fuel intake by km/lit