It’s amazing to me ,as how far these UTVS are behind the automotive technology.The fuel rails should have psi returns.the ecu s should have more input sensors.a knock sensor would be invaluable, run the timing up, lean it out, once u detect preignition,Back off.mass airflow pretty basic.and realize I haven’t worked on vehicle s since 2002
Kinda makes you think where they cut costs, my 93 cadillac has a more advanced efi system. However, Kawi isn't the only one guilty of this. Polaris's early efi on the Ranger etc used intake temp, engine temp, and barometric pressure to decide what fueling should be. In the end, it was basically a glorified carb with an auto choke. Our ranger wouldn't idle when it was sitting outside in the winter, had to keep on the gas for several seconds to keep it from dying. In the summer, idle would be rich. I don't think the KRX has any knock control or a wideband O2, maybe the Kraftwerks or dynojet guys would know more about it. If you want a good explainer on how efi works, Robot Cantina has several good videos on the subject with him installing an EFI kit on a Predator small engine.
BTW, the cadillac efi doesn't let you foul plugs from cold starts. You can start and stop the engine all day cold and it doesn't care. I think the hot fuel situation has an effect on hot starts and may lead to fouling plugs, but I haven't considered nor know enough on the subject to make that determination. I'm 99% sure the longer the engine cranks, the more fuel it adds (to a certain extent) until the engine starts. Heat soaking also can increase intake manifold temperatures which the computer tries to compensate for, then gets cool fresh air when cranking and can't react fast enough. But, I have no idea if the ECU even takes intake air temperatures into consideration in its fueling strategy. It's very easy with a limited efi system for something insignificant to cause "weird" issues. It would be nice if someone knowledgeable would do a writeup on how our ECU operates in this application and how advanced/limited it really is.
In reality, I just have to wonder why Kawi designed the engine to put the exhaust at passenger cabin instead of exiting out the back side of the motor, and have the intake on the opposite side. The whole thing really screams "we had a design for a motorcycle/atv engine and made it work, packaging and heat doesn't concern us, get this high margin product out the door". Of course, what other powersports/automotive product doesn't suffer from the same fate. The answer is: none of them.
