Johnny, we in open loop are 'load based' as in the intake vacuum is the load and the throttle position is other number to compute for load demand to throttle opening. That's open loop.
In closed loop, we have an 02 sensor that senses air not fuel. So when fuel is entered, this throws off what air it was reading in sort of a glow plug kind of way. The fuel hits the glow [inside] and cools the tip outside. There is your ping in heat to value. The glow plug is like a toaster in a fixed position and the glow goes right back to its heat range and ping, another slam to the floorboards, cooler even still, do something opposite! This sends a math computation to send the fuel metering to richen or lean the system vs rpm speed demand. Same principal we see vacuum demand and a thermometer in the intake, no glow, just push the merc in the tube and [move up to] cool the hot wire tip going up to the ECU kind of meguyver hub x-ray into that sensor. This is how it sees demand and adjusts 'off of a' fixed setting. So a glow plug (say a car's MAF = mass air flow) is in the intake and says, 'oh it's cold out, lets run the number in a math to electrically run opposite to watt is coming in. It's a pulse of a resistance to change the number to change the fuel flow. Send it up the wire to the INPUT side. For argument sake, rich uses a high value and lean runs a low value of electrical inputs from a sensor. I feel cold air that hits my glowing toaster kind of looking proportional outside that MAF cage so you won't burn yourself is that wire sending in a number like a bulb is fixed to the watts, fixed to 12v and it's a steady glow, yes? Theory says up the wire are many numbered INPUTS from that wire sensor cooling it, where the molecules expand/contract along with the ambient condition and now it's lean to match an expanded air to fuel ratio, or richens to meet the cold air cooling an electrical number the processor now can compute off this base number.
Enter the powercommander. This unit has the ability to use an 02 sensor. The wide band call it, can detect the quality of tune in a faster way so the driveability is in check and the fuel trim is not going to run rich like a carb with a fixed jet. If we climb up a mountain with less air to mix with the fuel, we run rich with the carb. The O2 detects less air and sends in less fuel. It's a simple opposite kind of electrical move. Man can manipulate the fueling via an electrical system that can sense(or) heat change and this can be measured.
So as the 02 can be fixed for 14.7 or stoic [theory is zero emissions if stoic] then the map can be fixed to run any AFRatio. So the powcomdr is mapped at 12.9:1 ratio is the base map. That is now running open loop as no autotune (02) is being used. When the autotune takes it from there and refines the map numbers to this sort of seat of the pants, it's a better tuning status to the change [following] the environmental condition it's in.
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As far as the sensors go, the 02 is being slowly eaten away and the carbon to rust to condensation to its environment it lives, this would be something like a deteriorating sensor. The rest of the parts are pretty much bulletproof like a radio with the same parts its motherboard basically. And look how long those tubes last to now transistors... A looooong time.
However, heat thru them is going to burn thru the weakest link. So far, it's 8 years of a top model run and I do not hear component failure around here. So lets say we take out the 02 as an example. It just converted to open loop, yes? No sensor to monitor the fuel to air going past it. This is now in backup or open loop and where does our western 14 run at? 14a about. Where does the euro run at? 14a about give or take stoic. And thru the PAIR? 16a.
Say we fail at the throttle sensor, and vacuum [both] go out at the same time. There is this backup system call 'Method.' The bike now runs off of the absolute atmospheric pressure number called 1 atm, 760mmHg, 101.3... So there is a low to mid, mid to high kind of 0 to redline safe fueling. And between that line is the method used on both sides of low to mid and mid to high throttle openings. Same method saves open as is closed. Both use the math against the penultimate number... 14.7.
How close am I?
Tormenting the motorcycling community one post at a time
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