EFI tuning question

[MtnEX]

OK, you guys have been at this EFI tuning thing a while... so maybe you can help a Kawi guy out???

So please tell me what would cause one to do this???

Revs clean, runs good, but burbles as shown in the video with no load.

When riding it does it if you are steady in the throttle and start down a hill, or if you ease into the throttle when in a low load situation...

I know it has something to do with the fuel vs RPM and the fuel vs TPS logic... one or both are off and need adjustment...

It just has me tripped up and confused.

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[witech]

Have you adjusted the fuel up/down in the low range or calibrated the throttle?

[MtnEX]

Well, actually what I did was....

I added an intake system I built for the thing that gave me a massive gain...

I just hated to soil the thread right off with that info... as I was afraid I'd get the simple "it's lean" response.

I know it is probably still lean although I've added fuel.

What has me stumped is how to blend that out to get rid of the burble in low or no load situations.


I know the EFI uses both the throttle position and the engine RPM as variables in calculating fuel delivery. And I have the ability to adjust the fuel levels wherever I want, however I want in both logics... fuel vs RPM and fuel vs TPS.


One or the other needs to come up I think to settle this out. I just don't know which one is the "correct" way... if you know what I mean...


I "think" the reason it does this is the RPM variable of the equation is higher up the trim... while the TPS variable is lower due to lower throttle opening than you must have to achieve the same RPM with load on the engine.

So I am thinking... fatten up the fuel vs TPS... but the dang thing revs really clean as you can see... and it pulls like a raped ape.

That thought makes me want to instead fatten up the fuel vs RPM.


What is the right thought process and logic to use to proceed?

[witech]

From my experience a barble like that is to much fuel in the low end. Can you monitor engine rpm and throttle position like on a power commander and adjust fuel blocks in real time? Im not familiar with your system. Just power commanders and Dobecks.

[MtnEX]

Originally posted by witech
From my experience a barble like that is to much fuel in the low end. Can you monitor engine rpm and throttle position like on a power commander and adjust fuel blocks in real time? Im not familiar with your system. Just power commanders and Dobecks.

OK... I may have something too rich?

That was the last thing I would have thought as I don't see any smoke or anything.

But yeah, I can see the possibility.
And here is where I see it...

I give it a little throttle in no or low load...
The RPM part then advances farther up the curve than with load...

So it burbles?


I was thinking the opposite... too little TPS vs fuel...

So, I could try changing the RPM vs fuel curve where it is more of a swoop at the bottom and less of a straight line up where it comes on slower?

Or do I need to look at the TPS part.
I don't want to discount that just because it revs clean.

[wrekd]

Mine is doing the same thing. It has to be a TPS issue cause I've adjusted the hell outta my fuel controller and can't get rid of it. I'll get a vid up in a little bit. (slow connection)

[MtnEX]

Well I'll be.... maybe we can end up helping each other...

So I checked my TPS voltage and it is a bit above specification. Adjustment has vibrated out of range I guess. The KFX is pretty darn picky about this tiny voltage level.

On my machine, this being high at closed throttle would enrichen the entire range on the fuel vs TPS... because it is telling the ECU the throttle butterfly is more open than it is.

I still can't exactly understand why it revs clean though... lol...

[MtnEX]

OH, and I don't have a fuel controller.

I have an adjustable/programmable aftermarket ECU.... this is how I can mess with all of the logics individually.

I am altering the actual variables for the calculations instead of piggy-backing and altering the result coming out of the ECU to the injector.

Just saying so I'm not confusing stuff with "terms" I am using.

[witech]

I went on the procom web site and downloaded the software. All I can say is we have come a long way .WOW.
Can I assume you just started with one of thier prebuilt maps and are having trouble guessing what the next move is to mod the mapping and timing to meet your needs?
You have some very powerful software to use and I would suggest just going out into a field and spending a couple hours just moving fuel and timing up and down just to get familiar with the programming. Mod the map it till it feels good. It would be best to hit a dyno for more accuracy and get those extra horse power .
One thing Im sure has to be done is the tps must be calibrated for the low and high voltages . Automobiles see the voltages and figure it out themselves but I think you might have to do it manually.
One other thing I also suggest is gettin gthe engine warmed up so your only tweaking the hot part of the map where you will be running most of the time.

[wrekd]

Here's my vid. Mine is messed up at idle though too. My idle is constantly fluctuating. It didn't start doing it until i put the +3 TB and Dynatek Programmable ignition on. I put them on at the same time so I don't know which one was actually doing it. I have the ignition disconnected right now but i tore my quad apart for some cleaning and maintenace so I won't be able to mess with it (TPS) until its back together.



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[MtnEX]

Wow... it's exactly the same.

You have a touch more of it at idle than me... but it's the same. Yours revs clean too.

Does it run good under load?
Mine does.
It's weird.

[MtnEX]

witech,

Yeah it's real real nice... and I have had excellent results to date.

This particular setup just has me stumped a little.

I tried a little of everything... but it has been there since I installed this custom intake I built... which really uncorked it on the intake end.

I've tried editing Procom maps, I've edited my maps, and I've done "scratch" maps. It came with adding the intake and has not gone away yet.

I know it has something to do with the calculation between Fuel vs RPM and TPS vs RPM.... their relationship.

It's off enough to show up when the engine load and throttle position are lower than when riding... in relation to engine RPM.

I've got it running really strong... but I bet it could be stronger.

[wrekd]

Originally posted by MtnEX
Wow... it's exactly the same.

You have a touch more of it at idle than me... but it's the same. Yours revs clean too.

Does it run good under load?
Mine does.
It's weird.



It runs great under load or if I'm steadily increasing acceleration. It only does it when I'm at a steady throttle position. It doesn't matter what RPM its at either. Which leads me to believe its the TPS thats out of adjustment. I already checked the resistance on the TPS and it checked out good. I just haven't set the voltage yet. So hopefully I can get the voltage in spec. If not I probably got a bad TPS.

[MtnEX]

Originally posted by wrekd
It runs great under load or if I'm steadily increasing acceleration. It only does it when I'm at a steady throttle position. It doesn't matter what RPM its at either. Which leads me to believe its the TPS thats out of adjustment. I already checked the resistance on the TPS and it checked out good. I just haven't set the voltage yet. So hopefully I can get the voltage in spec. If not I probably got a bad TPS.

You gotta bit worse case of the same thing than me.

I haven't noticed it under load except very low load, like holding steady throttle as I roll off a hill. And at idle it's only been occasional.

Hopefully we will figure out a solution.

[wrekd]

Well I adjusted my TPS today. When I first checked it, it was at 3.625. It supposed to be between .63 and .73 :eek2: ...So i set it to .68. I still got alot to do to the quad to get it back together so I can't test it yet. But I'm pretty sure its safe to say that was my problem...lol

[wrekd]

Its fixed!! Runs like a champ now!! Now I just gotta re-adjust my fuel controller and it'll be good to go. Its runnin a tad rich.

So I would say to get your TPS in spec and see if that helps. These things are so damn touchy you coulda bumped it off just by unplugging it and plugging it back in.

I'll have a vid up in a little bit.

[MtnEX]

Originally posted by wrekd
Its fixed!! Runs like a champ now!! Now I just gotta re-adjust my fuel controller and it'll be good to go. Its runnin a tad rich.

So I would say to get your TPS in spec and see if that helps. These things are so damn touchy you coulda bumped it off just by unplugging it and plugging it back in.

I'll have a vid up in a little bit.

The TPS on the KFX... or mine anyways... is sooo touchy. It has a very tiny range of adjustment to be in spec and you can easily move it farther than that trying lock it down after you set it.

Mine was high but not as high as yours. I got it back in spec, and fired it up.

I ran it in a clean environment without the intake and it was still doing it's thing. Seemed like worse to me. I tried doing the fingers over the tube thing to see if I could restrict it rich and make it worse.... but I didn't have much luck with that operation... just couldn't get that right and keep it right long enough.

Didn't get to check it with my intake back on. It got too late.


But you make me think to tame down my Fuel vs TPS curves although it seems counter-intuitive to what's been happening.

[wrekd]

My vid don't want to download to Youtube for some reason. I'm gonna give it another shot though.



I'd say do the obvious and check for any air leaks and if there isn't any I would start by richening it up on the low end to where you know its running rich and then backin it off little by little and see if it gets any better. Can you adjust it while its running?? Also is there an IAT sensor on your intake??

[MtnEX]

No, I can't make adjustments on the fly like you can with a piggyback fuel controller.

Yes I have an IAT sensor and an IAP sensor.