Project Electronic Fuel Injection

[baddi]

Hey guys, it has been a while since i started this project but because of school (and parties) i havent installed it before now.

It is now installed and running, but it has very high idle speed with fully closed throttle and the screw which lets air bypass the throttle is also closed. The idle speed was 5000 when i started it and then dropped to 3000 after the warm-up sequence ended, but this was still very high, so i did the rough tuning and tuned it down to half the fuel globally. This way it was only 3000 when the warm-up was in progress and then 1400-1600 when it was ended, but it was still kinda odd in the way it acted. See this video:



At first i was a little afraid to give full throttle as i dont know if the standart calibration gives the right fuel/air ratio, but even with 40 % throttle it was almost as powerful as the standart carburator, so i'm thrilled by even the thought of this kit's unseen rage.  

Apperently ignition timing can also be the diffrence between 2000 rpm or 5000 rpm with only 3,1 milliseconds of fuel, so this kit has the potential to be a real beast when it comes to power. Let the tuning begin!  

[baddi]

You can ignore almost all from the last post, as i have just learned that it might just be an air leak causing that much trouble as the system tries to keep the right fuel/air ratio and still hold back the rpm. :p

Can you believe it, it was only a single line of text saying this in an "updated tuning guide". Thats why i missed it, i guess.

I will try to look for air leaks and fix it tomorrow.

[whiteknight]

nice one man, once you fix the problem you will have it running as smooth as angel delight.

[baddi]

It seems as if it is not an air leak, as the rpm doesnt drop when i spray water on the places where i could suspect leaks.
The spark plug is as black as an african tribe, so i will tru to decrease the amount of fuel to get the idle rpm down.

Let the tuning begin!

[Kenho21]

That is badass! But from the trials and tribulations I have experienced just trying to get mine tuned and running right with your "average" upgrades I can already tell I would be losing a lot of sleep if I attempted something like that.

My hats off to ya for even having the balls to attempt it let alone actually getting it to run hahaha

[baddi]

That is badass! But from the trials and tribulations I have experienced just trying to get mine tuned and running right with your "average" upgrades I can already tell I would be losing a lot of sleep if I attempted something like that.

My hats off to ya for even having the balls to attempt it let alone actually getting it to run hahaha

As it would still idle high and run (but not as good when the throttle is turned) with global enrichement factor at 0,5 (1 is normal), i know that cutting the fuel down to three quarters or half is possible, but that it shouldnt be cut as much down all over the line, so so far its kinda guessing, but it will be much easier as soon as i find someone to weld a nut to the exhaust, so i can use the O2-sensor to tell me rich or lean and to let it self-tune.

Yesterday i drove to work and back, which is 30 km, with the standart calibration (which is a little too rich) and with only 30-40% throttle and even though it was a little slow in accelleration (due to the low throttle), it had the power to hit a topspeed of 63 and keep a stable speed of 57 (all gps measured as speedometer is 10-15% off), which tells me that this has potential to have alot more power than the carburator, as this is in the high end of the variator, but not fully outgeared.


The tuning i'm doing now is playing with the Volumetric Efficientcy table, which the ECU uses to calculate the needed amount of fuel. I'm downing the values by 0,1 (which is alot as the VE table has values from 0,4-0,8), which means that the value will be cut by 1/4 at low rpm and low pressure but only cut by 1/7 and 1/8 at higher rpm. If this doens't help me, i have got a backup of the original calibration.

[Kenho21]

The whole more gas + more air = more power thing just got a whole lotion more complicated...

[LoveMyKymco]

You need to do a pressure and vacuum test before you keep guessing between air leak and bad A/F.
While in college I use to rechip ROMs in car ECUs or update EPROMs, ps2,3 xbox, robotic iFles, etc. Ive built quite a few efi set ups, but the problem is the software it utilizes is so different due to copy right lawsuits. The O2 needs to be installed before doing the set up honestly. and if not you need a data logging wideband to co ordinate with the software along with a hand held tach to pin point your A/Fs.

Maybe I can give a bit of advice in a common set up up table. Take note it may not be exactly like your software but replace your terminology with like terms from my base.


First thing that needs to be done is turn the 02 feedback off. Open Idle/Idle target base table/Table. This is where you will set the desired idle rpm.
Lets start with these settings.

-40 to 68=1400rpm
86=1350rpm
104=1325rpm
122=1300rpm
140=1250rpm
158 to 248=1200
This will give a 1200rpm idle when the engine is warm. 158F+ ECT and 1400 when cold -68F ECT.

Get the engine started and idleing somewhat steady. You may have to baby it until you can get it to steady out from the idle feedback working. open idle templates.

You may have an Idle Learned value of +/- 5. This is normal at this point. Adjust the fuel table until you can at least keep the AFR in the 14's when the engine is at full temp. At this point the idle should be around 1200rpm. Monitor the idle learned value,Adjust the Idle% vs Target graph/table at the 1200rpm point up if the feedback is negative or down if the feedback is positive. Adjust unitl the feedback value is staying around 0. Now, go back to Idle/Idle target base table/Table. Change the 158 to 248 value to 1300rpm. The engine should idle up, give is a few seconds to stablize. Adjust the Idle% vs Target graph/table at the at the 1300rpm point until it is around 0. Do this all the way up to 1600rpm adjusting the idle% at every rpm point so that at all commanded rpm points the idle feedback is around 0. Change the commanded idle (Idle/Idle target base table/Table) to 1100 rpm if it can idle some what stable adjust the Idle% until you have near 0 feedback (idle feedback value). Do this at 1000rpm,900rpm,ect. or until you reach an rpm where the engine wont idle. Once this is done you will be able to see the "curve" of the Idle% vs Target graph. Take the rpms point the engine would not idle at and smooth them making the table have a consistant curve. example: 1000rpm=35% 900rpm=33% 800rpm=30% an so on.
Also, adjust the 1700rpm-1800rpm the same way. Make 1900rpm and up all the same % making the curve go flat at 1900rpm-3000rpm.

Now set the idle base back to 1200rpm. At this point the engine should be idleing fairly well. Turn the engine off. Start with these values.
High idle car speed=255
High idle rpm offset=0
High idle wait time=0
Idle off if tp over=2%
Idle on if tp less=2%
Idle feedback above rpm=400rpm
Idle feedback below rpm=1800rpm

Go to Configure/ECU setup/Set throttle range. Follow the instructions to setup
the TPS.This is where it gets tricky!!!!!!!!! You should now have a tps reading of 0.
Go to Setup/Sensors/Throttle position sensor/Options. Monitor the throttle % and move the TPS min. voltage down in .02 increments until the throttle % shows around .5% Example: 0.70 / 0.68 /0.66,ECT. If the throttle % EVER shows 0 some of the idle tables will be turned off!!This is a problem with the software variances and took me years to figure out. The throttle % will change from when the engine is cold to when it is warm. The trick is to never let the Throttle % read 0. If it does the idle goes all to hell. At the same time throttle %must never be above the
2%. Watch it during cold start and when the engine is hot, adjust accordingly to keep is between .5-2%

Go to the Ignition table and set the all the cells near the where the engine is idling to 10 degrees. So below 1500rpm and -5psi will be 10's.... Open Idle/ Advanced idle/Templates change these values.
Idle park target=48%
Idle feedback minimum= -5%
Idle feedback maximum= 5%
Idle feedback rate= 588
Idle extra <12 volt= 0

Open Idle/Advanced idle/Ign vs idle rpm table/Table Use these values.
-325 to -125= 10
-100=9.84
-75=8.44
-50=6.33
-25=4.22
0= 0
25= -3.52
50= -5.98
75= -6.68
100 to 300= -8

note: Im not sure if all of the above settings will work for your software. This is simple Tuning for single cylinder honda 2t using 24mm TB, 42 ccm fi, and MS1 with MS2 software.

If you reopen the Ign vs idle rpm graph you will notice is has some steep curves now. This is what makes the engine idle at a steady rpm. The base ignition timing
is now 10 degrees but when the engine idles up it will retard timing and idles down it will advance the timing. This way the ignition timing can control the idle rpm instead of just using the iac motor. This gives a great idle. hot, cold high,low,turning, everything. This also fixes some cold start issues. If the engine goes to stall the timing will ramp up and rev the engine back up before it stalls.
this reaction happens MUCH faster then an iac motor could ever respond.

Start the engine and let the idle settle, you should notice the ignition timing moving around a lot. More if it had big cams i would think. Mine moves from 2-18 degrees at idle. But now you should have a rock solid 1200rpm idle.
Go back to the idle target table and move the 150F-248F to 1100 rpm and see how it idles also making sure the idle feedback is near 0.
-3 to +2 is ok. It will be best if you can keep it between 0&-2 as it will encourage a higher idle before the feedback responds.
Now try 1000rpm. 900rpm,ect unitl you find the sweet spot that your happy with.
With cams i wouldnt go lower than 1000rpm. Mine will idle at 1000rpm but its very rough being as it needs more scavenging.
Now open the 02 feedback table and set the idle & drivability area's to 14.7AFR and turn the 02 feedback on after you get it welded in.

[zombie]

Yeah!!! Do all that!~


NICE!!!

[Vivo]

or call a marine mechanic on scooter to do the stuff..

[zombie]

Two Maybes?? I would still be looking for that air leak... / You may need a smaller injector

[baddi]

To Lovemykymco: Thanks bro! Even though my software is totally diffrent, in many ways, i will try to see how i can incorporate that in my tuning, but i only have one field called "desired idle rpm", so this is not dependent on temperature and all the sensors are calibrated from the producer, who are also the same who has made the software.
When the tps = 0, the tps based tables will go offline but the Volumetric Efficiency table are only dependent on Manifold pressure and rpm, so i guess this is the one i should adjust to get the fuel down. 

But you might be right, that i should search for an air leak even more. The other day i were doing some mechanics work for a guy, and found out that his exhaust valve were burned to half thickness in less than 13.000 km, so i will check my valves for leaks asap.

I already have the smallest injector, 38g/min. 

[LoveMyKymco]

You can have whatever size injector you want, the ECU will down cycle it on closed loop. Just like any efi system built after 1990 it will balance itself out at stoich. if its meant to run on 28cc/m and you put in a 56, the ecu will down cycle as far as it can then it will change the timing to make it stoich. Id say around 89 was when everyone used mass produced digital efi vs analog efi like ones that used flapper style AFMs and speed density junk. Yours is digital being as it has a MAP sensor. With old flapper style you could change the armature tension to use bigger injector or add a resistor, then came along digital and solved many problems.
With tunable efi you can even change the duty cycle yourself but in the end it will learn its 14.7/1 ratio anyways and should supersede your input once it goes to close loop. Your idle is controlled through your VE table, MAP sensor(pressure sensor) and TPS input, I would try setting your TPS position to .5% instead of 0, or like you said it will go offline and its just basing your idle speed off of preset maps if youre not able to access the fuel parameter map. Your VE table is for simple base calculations and more than likely controls the ignition spark timing as well.
If I were doing this swap I would start over from the beginning and bring everything back to base out of the box settings. If you can save your current setting I would do this as well. Make yourself a folder for them as you will have a lot.
I would make it so it cant hold an idle and work up, not down. Doing it this way it will force the numbers on the VE table to make themselves clear and you will know your absolute base.

If the program is open to download i can DL it and run it through an emulated program if I can find the one for yours. Ill do a little research later on tonight.

[LoveMyKymco]

Ultimately I think you have an air leak tho and should check this first. Even if you had a burnt up exhaust valve(or poor adjustment) it still wouldnt make it idle that high, it would probably not idle thanks to overlap.
Only a couple things will cause it to idle high and I honestly would think air leak first for sure.

[baddi]

Today i've made an arrangement with an automechanic to weld a nut to the exhaust so i can finally fit the lambda sensor. I will have the exhaust back on monday and will continue tuning next week.

I tightened all nuts today to eliminate air leaks between the throttle and the engine and the idle rpm came down to 2200 with the idle screw fully screwed in.