Tuning the RX4's Fuel Injection - Page 3

Lukas · 04-24-2022, 06:57 PM

Quote:

Originally Posted by Bob Kelly

But the problem is that the bike Runs too lean from the get go !!! it could handle more fuel throughout the entire band ! .... the question is how much resistance is needed and where do I put it ? LOL I'm willing to add a resister in line to richen up my bike I don't think a bike should have a white plug in it...but that is how they are set up... !
.....
Bob.....

These bikes do not have catalytic converter but catalytic converter mesh in the muffler which is an ordinary straight pipe and the mixture on the lower parts is set to very poor to make the exhaust as clean as possible which results in lack of power in the lower parts of the rpm my RX3 had power only from 6000k rpm now after map tuning by Italians the power is from 3000k rpm. At the beginning, it is quite a strange experience for someone who is used to riding this motorcycle, so the map must be tuned, i.e. injection time, fuel quantity and ignition timing, that all sensors make corrections to the amount of mixture and ignition timing in relation to the basic map and work together which means that a change in the signal of one sensor can cause something in the form of misinformation for the ecu which may result in a check engine light up.

JFOlivier · 04-25-2022, 11:38 AM

Lukas by adding 100 ohms to the input air sensor all you would be doing is telling the ECU that the temperature is 10 degrees F cooler than it actually is. This does not change unless the temperature increases during the day and if it does the sensor will decrease in resistance and the temperature reading will continue to be 10F cooler than actual. So in effect the sensor will still increase and decrease but the ECU will just believe it is 10 degrees cooler. What the effect of this will be on the EFI is hard to tell but i think with just 100 Ohms in series with the sensor it will remain in range. Of course this is with the sensor on the Lifan e-pect not sure about the sensor on the RX's but that is easy to check with a multimeter.

Lukas · 04-25-2022, 12:10 PM

The air intake temperature sensor influences the correction of the fuel mixture parameters and the ignition advance angle. Properly functioning power system and efficient sensor is very important to reduce fuel consumption, harmful exhaust emissions and improve engine performance. The intake temperature sensor is calibrated and its parameters must coincide with the parameters of the lambda probe in the exhaust manifold, if you change the value of the output signal, the computer on the one hand will get information that the air density is different and will give a different dose of fuel, but it will not be correct and the lambda probe will give a wrong result to the ECU please tell me what is your goal, do you want to increase engine power maybe I can help you.Do you have a picture of your ECU.

JFOlivier · 04-25-2022, 03:10 PM

Lukas I am happy with my Lifan x-pect but would like to learn a little more about ECU,s and their operation. I will be setting up ECU hacker so that I can download information from my ECU which is a Hunier EFI 9.0. Also thought about putting a oscilloscope across the fuel injector and try to measure the pulse widths and by adjusting a 100 Ohm potentiometer in series with the IAS see if the pulse width varies by increasing the resistance. Just trying to learn by observation.

Lukas · 04-25-2022, 03:47 PM

I think it is safer to run the tests from within the software, because you can change the parameters under the control of the ECU based on real data, by changing the resistance of the signal the data coming to the ECU will not match reality I think you can play with the AFR. On the internet you can find many products for cheating ECU by connecting various types of emulators that falsify the signal, but in fact it is just a bulshit, because real tuning always involves change of map calibration, because in case of damage to one of the sensors Ecu should go into emergency mode, which involves loss of power, and if any system such as change of cylinder capacity, change of exhaust or intake was changed then the emergency map can damage such an engine.Because the mixture will be too rich or too poor.

Lukas · 04-25-2022, 07:11 PM

Quote:

Originally Posted by JFOlivier

Lukas I am happy with my Lifan x-pect but would like to learn a little more about ECU,s and their operation. I will be setting up ECU hacker so that I can download information from my ECU which is a Hunier EFI 9.0. Also thought about putting a oscilloscope across the fuel injector and try to measure the pulse widths and by adjusting a 100 Ohm potentiometer in series with the IAS see if the pulse width varies by increasing the resistance. Just trying to learn by observation.

I would be very grateful if you would describe the observations you made during the experiment with the oscilloscope, because I have an old BMW from 91 and unfortunately there is no way to connect it to the computer and check why the engine runs unevenly and here the oscilloscope could help and any knowledge of this type is valuable to me and I hope that you will not pop out check engine during the tests.

JFOlivier · 04-26-2022, 01:37 PM

Lukas as soon as my 100 ohm potentiometers and plugs arrive I will dig out my old scope and try out ECU hacker and see what the results are like. I think if the engine light comes on with a fault reading as soon as you correct that fault the light goes off. I ran the bike with the IA sensor unplugged and it ran with the fault light on and once I replaced the sensor the light remained off. The Hunier EFI 9.0 I guess is the same as the Lifan EFI 9.0 I could not find a plug to fit the EFI diagnostic female plug so will have to make one up to connect the 3 wires involved One is a positive another is ground and the last is the in and out data so we wll see how that goes.

Biker_Andy · 04-27-2022, 08:13 PM

I would recommend replacing the potentiometer with an actual fixed value resistor once you find an adjustment you like. Measure the resistance of the Pot when it's adjusted property and the wires are removed. Then permanently replace it with an actual resistor of around the same value. Potentiometers value change depending on temperature, wear and contaminates. Vibration could also wreak havoc temporarily changing the value or even creating an open circuit for a millisecond. Plus you don't want to make your motorcycle less reliable or add something else that can easily fail. Fixed resistors are far less effected by temperature, totally water, dust & vibration proof and almost never fail.

If you want adjustability then putting a fixed resistors in parallel with a Pot is a better idea because then if the Pot fails you don't have an open circuit condition.

JFOlivier · 04-28-2022, 08:56 AM

Fitted the 100 ohm pot in series with the IA sensor thermistor and connected my 50 year old oscilloscope to the injector and ran the bike with the full 100 ohms added to the IA sensor. The x-pect now idles beautifully and revs up fine unfortunately the scope is a bust as all I can see are spikes from the injector that are so poor that I can not determine anything worthwhile from them. As soon as the weather improves a little I will take the bike for a long ride and see if I can feel any difference or if the ECU is going to complain. The pot is set up with 6" of twin core cable with a 2 way plug male and female either side so the IA sensor is removed one end of the pot plugged into where it was and the IA sensor then plugged into the other end of the pot cable, so the pot can be removed and a 100 ohm resistor can be easily added. The next step is to fit a new 4 way plug onto the 3 ECU wires from the ECU diagnosis plug

Bob Kelly · 07-19-2022, 12:53 PM

pyoungbl.... I hate to rain on your parade ...but in all my years changing jets and messing with bikes I have NEVER seen a condition where the cylinder is "Washed dry" of lubercant
that simply cannot happen and still run ! even with a badly sticking float where I could get the bike running by pushing it down a hill and dumping the clutch the spark plug will fowl out before any damage to the cylinder in such a wet condition....
so I think your fear is unfounded of washing the cylinder dry .... and sizing a piston or worse....
.... that being said I have to agree that the Resistor idea is not the best idea on the planet... like you said the fuel flow /Air ratio does waver alot, in a carbed bike. although not from the reading of the ECU in running condition...that fuel air ratio there is rock solid and does not deaviate at all with a carbed bike it does but as far as I can see the Fuel injected bike does not wonder at all with it's fuel air ratio ! and I was quite suprised at that..... but if you make it richer by changing the tempiture you will only make it very slightly richer.... probably not enough to even notice. and doing that will change how the ECU handles other things like Idle and perhaps deceleration.
.....
the ECU is a very precise instrument ! you don't want to be "Fooling " a sensor as almost every sensors has triple duty !
....Until I get to the point where I can change settings with no problem on my ECU I will leave it stock.... but I am sure already that there are a few settings where I can get a bunch more power from the thing.... doing that will be a major challenge !
....
learning to Run the HUD ECU HACKER program itself is the hardest part so far...there is a steep learning curve !
....
Bob........

pyoungbl · 07-19-2022, 04:35 PM

Bob, I can understand your thought process...if you have not personally experienced the problem it is suspect. With that said, I have personally experienced the effect of running super rich due to the resistor gadget. On a 600 mile trip to Florida my Norge started running like crap and finally went into limp-home mode by the time I got to FL. I was lucky enough to find a replacement O2 sensor for the trip home (after I removed that damned resistor). My O2 sensor was so carboned up I doubt it could have been salvaged. I'm also aware of a case where the engine did lock up due to running super rich...traced back to the resistor problem. Yes, that is second hand info but came from a trusted source.

A good running ECU map is the very best solution to any performance issue. I hope you can come up with a map that you are happy with. You are braver than I.

JFOlivier · 07-19-2022, 05:45 PM

pyounbl, After fitting that 100 ohm resister in the X-pect it ran fine and I would expect very little change in the F/A mixture which when the bike reached operating temperature and went into closed loop operation the O2 sensor would rule the F/A ratio. Quite frankly I felt a good difference just moving up from regular to mid grade fuel. On your setup where you carbonned the O2 sensor whatever you did must have been out of the ECU'range therefore the limp mode or the was a blockage in your air intake that would cause the system to run so rich that you would cause heavy carbon deposits.

Bob Kelly · 07-20-2022, 03:22 AM

JFOlivier ;.... LOL Pyoungbl is not your average dummy he is sharp and if he said the resistor caused the problem I believe him.... something like a sock getting sucked into the intake would not get by this guy....
it's interesting that you guys have used a resistor in the X-pect or at least tried it
....
I agree that changing the information in the ECU is the only way to do it correctly
the problem with that idea is that most all of those settings in there change 2 or 3 settings by their value..... so it's Kind'a hard to find a setting that isn't 3 combined sensors that are grouped together to make the one setting work like the Fuel /air ratio for example. so changing just one value sounds like an easy task but doing so will effect 2 or 3 unrelated things....
for instance. if I change the ambiant tempiture to be 20 degrees colder than what is reported to the ECU (which should be a fairly simple task) that will effect everything that USES tempiture in it's calculations such as Idle, Fuel/air ratio, and a dozen other things in there that uses air tempiture in it's calculations....
so is it a viable way to change the Richness of the bike when it is running..... NO not in my opinion....you don't want to change something at the base of the tree and have it branch out, what you want to do is go to the other end of the tree and change the indivudal leaves of the tree.... that way nothing else is effected. work your way in from the leaves of the tree ,don't start at the trunk where you will effect everything in the tree.... in other words go to the source.
.....
You can't suck out more fuel from the float bowl on a fuel injected bike.... there is no float bowl ! so plugging the air intake would not cause it to run richer but the effect would be close to the same and the engine would be a dog it would not get it's full volume of air so the amount of fuel in there would seem richer-per-volume but the performance would be way down as the engine is running on much less than it's normal volume per power stroke...
the Rat's Nest of commands inside the ECU is a tough one to decipher and I'm still working on finding which ones that I can actually change without effecting everything else ! ....what I am looking for is the "end effector" and they are not labeled ! LOL
.....
Bob....

Lukas · 07-20-2022, 08:22 AM

I would just like to say that you need to change 4 values at one time:
1) The amount of fuel.
2) The amount of air.
3) ignition advance angle.
4) fuel injection time.

To do this you do not need to have specialized knowledge, but to do it the way it should be done you need to at least read any book on tuning internal combustion engines, and preferably have practice from a tuning workshop in any other case the engine or its components will be damaged, because it works in a system of communicating vessels and cheating in the way of distorting the real parameters is a BIG mistake a simple example.
Give someone a mask of oxygen, but the indicator clock on the cylinder cheats and understates or overstates the real value and the person using the cylinder will either suffocate or the pressure will burst his lungs and the same is true in this case cheating the value harms the engine as knocking combustion will occur, the engine will run very well, but after some time it will fall apart 30 euros costs injection map and not knowing any tuner this is the only solution and would like to remind that if someone overclocks the engine himself and it gets damaged, probably his EGO will not allow him to admit his mistake, so I would advise to approach garage specialists with detachment.

pyoungbl · 07-20-2022, 12:03 PM

JFOliver, the spoofer i used was supposed to be set up specifically for my bike. I'm not convinced that was actually the case. As for the intake, there was no obstruction as evidenced by the fact that I could ride the bike home and even for the next 20-30K miles with no issues once I replaced the O2 sensor. My bike was just running so rich it overwhelmed the ECU, thus the limp home mode.

04-27-2022, 08:13 PM	#38
Biker_Andy Join Date: Oct 2016 Posts: 347	I would recommend replacing the potentiometer with an actual fixed value resistor once you find an adjustment you like. Measure the resistance of the Pot when it's adjusted property and the wires are removed. Then permanently replace it with an actual resistor of around the same value. Potentiometers value change depending on temperature, wear and contaminates. Vibration could also wreak havoc temporarily changing the value or even creating an open circuit for a millisecond. Plus you don't want to make your motorcycle less reliable or add something else that can easily fail. Fixed resistors are far less effected by temperature, totally water, dust & vibration proof and almost never fail. If you want adjustability then putting a fixed resistors in parallel with a Pot is a better idea because then if the Pot fails you don't have an open circuit condition. __________________ Electrician & Electronics Tech 2014 Honda CB500XA 2016 CSC TT250 1976 Honda CJ360T 2022 Honda Navi
	0

07-19-2022, 12:53 PM	#40
Bob Kelly Join Date: Jan 2022 Location: Weed, California. Posts: 271	pyoungbl.... I hate to rain on your parade ...but in all my years changing jets and messing with bikes I have NEVER seen a condition where the cylinder is "Washed dry" of lubercant that simply cannot happen and still run ! even with a badly sticking float where I could get the bike running by pushing it down a hill and dumping the clutch the spark plug will fowl out before any damage to the cylinder in such a wet condition.... so I think your fear is unfounded of washing the cylinder dry .... and sizing a piston or worse.... .... that being said I have to agree that the Resistor idea is not the best idea on the planet... like you said the fuel flow /Air ratio does waver alot, in a carbed bike. although not from the reading of the ECU in running condition...that fuel air ratio there is rock solid and does not deaviate at all with a carbed bike it does but as far as I can see the Fuel injected bike does not wonder at all with it's fuel air ratio ! and I was quite suprised at that..... but if you make it richer by changing the tempiture you will only make it very slightly richer.... probably not enough to even notice. and doing that will change how the ECU handles other things like Idle and perhaps deceleration. ..... the ECU is a very precise instrument ! you don't want to be "Fooling " a sensor as almost every sensors has triple duty ! ....Until I get to the point where I can change settings with no problem on my ECU I will leave it stock.... but I am sure already that there are a few settings where I can get a bunch more power from the thing.... doing that will be a major challenge ! .... learning to Run the HUD ECU HACKER program itself is the hardest part so far...there is a steep learning curve ! .... Bob........ __________________ It's too late when you've gone too far !
	0

07-20-2022, 03:22 AM	#43
Bob Kelly Join Date: Jan 2022 Location: Weed, California. Posts: 271	JFOlivier ;.... LOL Pyoungbl is not your average dummy he is sharp and if he said the resistor caused the problem I believe him.... something like a sock getting sucked into the intake would not get by this guy.... it's interesting that you guys have used a resistor in the X-pect or at least tried it .... I agree that changing the information in the ECU is the only way to do it correctly the problem with that idea is that most all of those settings in there change 2 or 3 settings by their value..... so it's Kind'a hard to find a setting that isn't 3 combined sensors that are grouped together to make the one setting work like the Fuel /air ratio for example. so changing just one value sounds like an easy task but doing so will effect 2 or 3 unrelated things.... for instance. if I change the ambiant tempiture to be 20 degrees colder than what is reported to the ECU (which should be a fairly simple task) that will effect everything that USES tempiture in it's calculations such as Idle, Fuel/air ratio, and a dozen other things in there that uses air tempiture in it's calculations.... so is it a viable way to change the Richness of the bike when it is running..... NO not in my opinion....you don't want to change something at the base of the tree and have it branch out, what you want to do is go to the other end of the tree and change the indivudal leaves of the tree.... that way nothing else is effected. work your way in from the leaves of the tree ,don't start at the trunk where you will effect everything in the tree.... in other words go to the source. ..... You can't suck out more fuel from the float bowl on a fuel injected bike.... there is no float bowl ! so plugging the air intake would not cause it to run richer but the effect would be close to the same and the engine would be a dog it would not get it's full volume of air so the amount of fuel in there would seem richer-per-volume but the performance would be way down as the engine is running on much less than it's normal volume per power stroke... the Rat's Nest of commands inside the ECU is a tough one to decipher and I'm still working on finding which ones that I can actually change without effecting everything else ! ....what I am looking for is the "end effector" and they are not labeled ! LOL ..... Bob.... __________________ It's too late when you've gone too far !
	0

07-20-2022, 08:22 AM	#44
Lukas Join Date: Jan 2021 Location: A small Polish empire Posts: 244	I would just like to say that you need to change 4 values at one time: 1) The amount of fuel. 2) The amount of air. 3) ignition advance angle. 4) fuel injection time. To do this you do not need to have specialized knowledge, but to do it the way it should be done you need to at least read any book on tuning internal combustion engines, and preferably have practice from a tuning workshop in any other case the engine or its components will be damaged, because it works in a system of communicating vessels and cheating in the way of distorting the real parameters is a BIG mistake a simple example. Give someone a mask of oxygen, but the indicator clock on the cylinder cheats and understates or overstates the real value and the person using the cylinder will either suffocate or the pressure will burst his lungs and the same is true in this case cheating the value harms the engine as knocking combustion will occur, the engine will run very well, but after some time it will fall apart 30 euros costs injection map and not knowing any tuner this is the only solution and would like to remind that if someone overclocks the engine himself and it gets damaged, probably his EGO will not allow him to admit his mistake, so I would advise to approach garage specialists with detachment. Last edited by Lukas; 07-20-2022 at 09:12 AM.
	0

04-25-2022, 11:38 AM	#32
JFOlivier Join Date: Nov 2020 Location: Northern Neck of Virginia. Posts: 164	Lukas by adding 100 ohms to the input air sensor all you would be doing is telling the ECU that the temperature is 10 degrees F cooler than it actually is. This does not change unless the temperature increases during the day and if it does the sensor will decrease in resistance and the temperature reading will continue to be 10F cooler than actual. So in effect the sensor will still increase and decrease but the ECU will just believe it is 10 degrees cooler. What the effect of this will be on the EFI is hard to tell but i think with just 100 Ohms in series with the sensor it will remain in range. Of course this is with the sensor on the Lifan e-pect not sure about the sensor on the RX's but that is easy to check with a multimeter.
	0

04-25-2022, 12:10 PM	#33
Lukas Join Date: Jan 2021 Location: A small Polish empire Posts: 244	The air intake temperature sensor influences the correction of the fuel mixture parameters and the ignition advance angle. Properly functioning power system and efficient sensor is very important to reduce fuel consumption, harmful exhaust emissions and improve engine performance. The intake temperature sensor is calibrated and its parameters must coincide with the parameters of the lambda probe in the exhaust manifold, if you change the value of the output signal, the computer on the one hand will get information that the air density is different and will give a different dose of fuel, but it will not be correct and the lambda probe will give a wrong result to the ECU please tell me what is your goal, do you want to increase engine power maybe I can help you.Do you have a picture of your ECU.
	0

04-25-2022, 03:10 PM	#34
JFOlivier Join Date: Nov 2020 Location: Northern Neck of Virginia. Posts: 164	Lukas I am happy with my Lifan x-pect but would like to learn a little more about ECU,s and their operation. I will be setting up ECU hacker so that I can download information from my ECU which is a Hunier EFI 9.0. Also thought about putting a oscilloscope across the fuel injector and try to measure the pulse widths and by adjusting a 100 Ohm potentiometer in series with the IAS see if the pulse width varies by increasing the resistance. Just trying to learn by observation.
	0

04-26-2022, 01:37 PM	#37
JFOlivier Join Date: Nov 2020 Location: Northern Neck of Virginia. Posts: 164	Lukas as soon as my 100 ohm potentiometers and plugs arrive I will dig out my old scope and try out ECU hacker and see what the results are like. I think if the engine light comes on with a fault reading as soon as you correct that fault the light goes off. I ran the bike with the IA sensor unplugged and it ran with the fault light on and once I replaced the sensor the light remained off. The Hunier EFI 9.0 I guess is the same as the Lifan EFI 9.0 I could not find a plug to fit the EFI diagnostic female plug so will have to make one up to connect the 3 wires involved One is a positive another is ground and the last is the in and out data so we wll see how that goes.
	0

04-28-2022, 08:56 AM	#39
JFOlivier Join Date: Nov 2020 Location: Northern Neck of Virginia. Posts: 164	Fitted the 100 ohm pot in series with the IA sensor thermistor and connected my 50 year old oscilloscope to the injector and ran the bike with the full 100 ohms added to the IA sensor. The x-pect now idles beautifully and revs up fine unfortunately the scope is a bust as all I can see are spikes from the injector that are so poor that I can not determine anything worthwhile from them. As soon as the weather improves a little I will take the bike for a long ride and see if I can feel any difference or if the ECU is going to complain. The pot is set up with 6" of twin core cable with a 2 way plug male and female either side so the IA sensor is removed one end of the pot plugged into where it was and the IA sensor then plugged into the other end of the pot cable, so the pot can be removed and a 100 ohm resistor can be easily added. The next step is to fit a new 4 way plug onto the 3 ECU wires from the ECU diagnosis plug
	1

07-19-2022, 04:35 PM	#41
pyoungbl Join Date: Feb 2016 Location: Portsmouth, Virginia, USA Posts: 632	Bob, I can understand your thought process...if you have not personally experienced the problem it is suspect. With that said, I have personally experienced the effect of running super rich due to the resistor gadget. On a 600 mile trip to Florida my Norge started running like crap and finally went into limp-home mode by the time I got to FL. I was lucky enough to find a replacement O2 sensor for the trip home (after I removed that damned resistor). My O2 sensor was so carboned up I doubt it could have been salvaged. I'm also aware of a case where the engine did lock up due to running super rich...traced back to the resistor problem. Yes, that is second hand info but came from a trusted source. A good running ECU map is the very best solution to any performance issue. I hope you can come up with a map that you are happy with. You are braver than I.
	0

07-19-2022, 05:45 PM	#42
JFOlivier Join Date: Nov 2020 Location: Northern Neck of Virginia. Posts: 164	pyounbl, After fitting that 100 ohm resister in the X-pect it ran fine and I would expect very little change in the F/A mixture which when the bike reached operating temperature and went into closed loop operation the O2 sensor would rule the F/A ratio. Quite frankly I felt a good difference just moving up from regular to mid grade fuel. On your setup where you carbonned the O2 sensor whatever you did must have been out of the ECU'range therefore the limp mode or the was a blockage in your air intake that would cause the system to run so rich that you would cause heavy carbon deposits.
	0

07-20-2022, 12:03 PM	#45
pyoungbl Join Date: Feb 2016 Location: Portsmouth, Virginia, USA Posts: 632	JFOliver, the spoofer i used was supposed to be set up specifically for my bike. I'm not convinced that was actually the case. As for the intake, there was no obstruction as evidenced by the fact that I could ride the bike home and even for the next 20-30K miles with no issues once I replaced the O2 sensor. My bike was just running so rich it overwhelmed the ECU, thus the limp home mode.
	0