I am not trying to make it lean or rich. I am only trying to set to the mid point and start from there.

How did you (or dealer) check for error codes, using the self-diagnosis mode or KDS?

Voltage input/output check on following sensors has been checked out OK?
Inlet Air Temp Sensor
Inlet Air Pressure Sensor
Water Temp Sensor

 

Everything has been checked 4 times over if not more, except the air pressure sensor... because I have no means to check that myself.

Everything passes. The only thing I found out was the crank position sensor... the resistance reads low on my meters. But the dealer says it passes every time for them. For me after several checks, it passes at the minimum resistance reading when hot immediately after a ride... but checks low cold... so I dunno. I think it is OK though, and unrelated due to the battery drain.

As for the codes, it's been checked both ways. Nothing is there because it NEVER records a fault code. I don't care what you do. Never did when I checked peak voltage of the crank sensor... cranked it over with the harness disconnected to test... which should have been a fault. Also tried a disconnected air temp sensor... just to see if it would store a code... and also to see if it would somehow run better in "limp mode" maybe.



I will put it to you this way on how rich this thing is... yesterday I installed full race exhaust... and I installed an air box eliminator intake, which takes the intake tract from the 3 finger pancake tube to a 3" ID tube. It should be so lean now it would hardly run... as it has no ability to adjust for any of this... I should have to have a fuel controller now... but it seems to run absolutely fine. Not one sound that would indicate it is lean anywhere.

So there is no wonder it will hardly run stock... crazy.

Anyways, when I get a chance, I will tinker with the TPS and set at 5 k Ohm and 6 k Ohm... But I think all that is going to do is make it so rich it won't run at all stock.


What say you about the battery issues? Has zero problems, then drains out of the blue down to around 11v in a short period of time. And don't say park in neutral, because we both know that is BS... It has been documented to drain in neutral as well. It's just a random event.

Also, what do you have to say about this.... 3 times so far it has failed to start back at all when the start button was pushed. The first time I thought it was the battery (no meter handy) and roll started it. The next two times, I realized that was not it. Battery checked out. Relays checked out. Switches checked out. Wiring checked out. Wire connections checked out. Starter checked out. Still nothing. Unplug the ECU for a little bit, plug it back in and it fires right up like nothing ever happened.

It's just weird.

 

Your quad runs rich, no disagreement there.
It also drains battery in short time, no disagreement there also.
In my experience, ECU is one of the most reliable parts and expensive parts on anything. That's why I am hesitant to replace before I try anything and everything else.

Running Rich
Have you done any check on the injector?
Remove from the engine, still plugged into the harness, and point the injector tip to a piece of clean paper and crank the engine over. Look at the spray pattern (nice & fine, not a stream), and also make sure it shuts off at once w/o dripping.

Battery Draining
Have you checked the amp draw using an ammeter?
There should be 3 relays (black plastic) under the nose cover (hood) right front of the handle bar, circled in red below.

One of them could be shorted (staying on even when engine is not running) and drawing current. Either using a volt meter or ammeter, remove/disconnect one relay at a time while monitoring the voltage/amp draw at the battery. As you remove one relay at a time and when the voltage/amp draw suddenly stops, that's the shorted relay.

Let me know what you find out.

 

Yeah, there are 4 relays under the hood actually, and they have been checked at least a dozen times. I was absolutely without question convinced I had a relay sticking that was killing the battery. But they are just not bad. I have checked per the manual, as has dealer... and I have checked them many more times... even checked them by applying voltage and taking it away many times to check for operation. And I know there is a main starter relay... and it has been checked too... but not by me.

Here are the facts about the relays though...

Starter Relay - It doesn't try to start by itself
Starter Control Relays - again it's not starting by itself and these have key-on power only

Fan Relay - This relay does have direct access to battery power. But the fan does not run when off if key is off.

Fuel Pump Relay - Very very good possible culprit. Also has direct access to battery power and if hung closed it would supply power to the fuel pump. But it's just not happening... not the case.

Common sense tells you that it's easy to replace and rotate these relays to rule them out. And they are ruled out.



As you know, the battery draw is very random... and it is hard to catch it drawing. But it does often have a static draw that is higher than it should be... but not over-night battery killing... just 3 times what it ought to be.... and then other times, it will have none at all.

When it does have above average draw you can hook up inline, and it is not a lot more when you turn the switches on... and not a lot less when you turn them off. And you can unplug everything on the machine and it will not go away... not until you unplug the ECU.

Never have been able to catch it and get a reading of the major draw. That I guess would take being connected to a high tech monitoring system, like they would hook a Mercedes to if it were having such problems.

Bottom line is though... only these things have access to key-off battery power...

Main starter relay (not starting)
Fan Relay (fan not spinning)
Fuel Pump Relay (pump not priming)
Regulator/Rectifier (checks out)
ECU

I am no electrical engineer, but I am no dumbazz either.

 

IMO, an average electrical engineer w/o any KFX400 knowledge can't even come close to an experienced quad tech.

If unplugging the ECU stops the amp draw, then it the culprit could be either the ECU or the main harness.

 

The main harness checked (ok) and the main harness has been swapped for new.
It wasn't that... and if it were, it would have to be on the white wire somewhere, or where it leads after the 10 amp fuses. So serious stuff like this should pop the 30 amp or one of the 10 amps.

It's the ECU.

 

Before moving the TPS to 5 k Ohm, I decided to try something else, just to see how far it was off.

I took off the stock intake... you know how restrictive that box and pancaked intake tube is!!!!

Well I took that off and put on a complete aftermarket intake. The air box eliminating type with high flow filter and huge intake tube. Massive difference in air flow.

I expected it to be too lean to run then. But it fired right up fine. I warmed it up, and revved it up some and didn't hear anything scary. So I took it for a little ride like that and ran it through the entire throttle range. Never heard any sign of being lean... no pings, pops or crackles, etc...

This is how my bad fouled up plug looked after that little test...

What do you think of that?
What do you see that tells you where it has been and where it is now?

 

I haven't heard from you about the injector. Have you checked its spray pattern and shutting off timing w/o dripping?

 

Well man, I hate to tell you this... but it appears the sensor resistance just "is what it is" and that's it.

In other words it doesn't really change from 4k ohm to 6kohm in the adjustment range of the sensor. It does not increase /decrease rheostat

If it's 4k ~ 6k Ohm... sensor good, if not sensor is bad.


All that changes in rheostat (relation to rotation) of the TPS is output voltage... and it's not even extremely adjustable. It only has a range of like 0.2v... maybe 0.52v to 0.72v (guessing)... but is still really hard to set and keep at the reading while tightening, accurately to 0.01v.

Range here is 0.58v ~ 0.62v (idle) to 3.7v ~ 4.1v (wide open).

 

Oh... and it's not just rich... it's way rich.

Like I can run an aftermarket fuel intake... huge tube, huge air filter... way higher flow.

Plus I can run a full race exhaust.

I can do that with no fuel controller and still be a bit rich.... crazy!



Anyways, I forgot to add that I set the TPS voltage down to 0.582v... as close to the bottom of the range (0.58v ~ 0.62v) as I could get.

This is as lean as it can go and still be in spec.