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Discussion Starter #1
Since these machines aren't carburated and therefore don't have a choke and they don't have MAF sensors, what determines how much air the engine gets on cold start-ups?
 

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There is an idle-air control valve but I think it and the injector pulse width is effected by the coolant temp sensor input to the ECM. Once it reaches a preset point it defaults to a preset map. On the 15+s with closed loop systems it still has that but it also had the O2 sensors to make adjustments to the pulse width.
 

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Since these machines aren't carburated and therefore don't have a choke and they don't have MAF sensors, what determines how much air the engine gets on cold start-ups?
Atvs usually use pretty simple FI systems. There's probably an air temp sensor and/or air pressure sensor that tells the ECU how much fuel to squirt in. It will inject a bit more fuel on a cold start due to a coolant temp sensor. Air will be whatever the atmosphere will provide at given elevation and temperature on a non-forced induction engine.
If it's one of the newer Brutes with the closed loop system, it may be a bit more sophisticated than that, but I've never heard exactly. Maybe someone with a 2015+ plus will chime in.
 

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Oops, NM and I were typing together.:wink2:
 

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Where's the IAC and what does Kawasaki call it?

Does it have two or does one bypass both throttle plates??
Sense it has two throttle bodies one would think it would need two. My Z only had one TB..and only one IAC... and it is right with it on the same housing. The manual should tell one what they need to know.
 

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Where's the IAC and what does Kawasaki call it?

Does it have two or does one bypass both throttle plates??
Sense it has two throttle bodies one would think it would need two. My Z only had one TB..and only one IAC... and it is right with it on the same housing. The manual should tell one what they need to know.
Apparently its really an IAC, idle air control - Kawasaki calls it a idle speed control - one on the same for them.

It looks like a divorced valve that allows air to bypasses both throttle plates for idle control.
 

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Where's the IAC and what does Kawasaki call it?

Does it have two or does one bypass both throttle plates??
Sense it has two throttle bodies one would think it would need two. My Z only had one TB..and only one IAC... and it is right with it on the same housing. The manual should tell one what they need to know.
I can't see one on an exploded parts picture is why I was wondering.
Maybe...they don't use one..maybe they are using the butterfly stop and the TPS to regulate the idle control...but I seem to remember someone having trouble with one once.
 

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Kawasaki uses one valve to control the idle air and calls it the ISC valve. It's located by the transmission shift lever on the right side of the machine. It's controlled by the ECU based on inputs from the TPS, intake air temp, intake air pressure, and coolant temp sensors. What problem are you having?
 

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Discussion Starter #13
Kawasaki uses one valve to control the idle air and calls it the ISC valve. It's located by the transmission shift lever on the right side of the machine. It's controlled by the ECU based on inputs from the TPS, intake air temp, intake air pressure, and coolant temp sensors. What problem are you having?

None really. It's just that if you start it when it's cold outside it seems to need a few minutes to "warm up." If you shut it off while it's still cold and try to restart it, often you need to give it some extra fuel via the throttle.
 

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they are programed lean, which mean it takes a while longer in the cold to start, on a efi needs more fuel via ejk or something like that for more fuel in the cold. the quads ive done that too start way easier and run cooler
 

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Kawasaki uses one valve to control the idle air and calls it the ISC valve. It's located by the transmission shift lever on the right side of the machine. It's controlled by the ECU based on inputs from the TPS, intake air temp, intake air pressure, and coolant temp sensors. What problem are you having?
I’m having trouble with acceleration, if I release the throttle it will turn off. And I doesn’t accelerate. I replaced the fuel pump it worked for like 1 day and it started to do the same. Any suggestions ?
 

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New pump is bad, or filters plugged.
 
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