Queensland Ken
Well-known member
Somewhat interesting.
The EFI system
The EFI system
Fuel injection 101
- Thread starter Queensland Ken
- Start date
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Pterodactyl
Well-known member
Thanks.
dcarver
Well-known member
The 2nd video is worthwhile watching
Niehart
Pie Smuggler
+2 - That was a great troubleshooting guide!
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If anyone wants to measure that coil back EMF voltage, a decent oscilloscope will do the job (easier to find than the tool he showed).
That second video is gold though, that's a lot of good information.
That second video is gold though, that's a lot of good information.
Ha! I thought the exact same thing when I was watching the video. No idea what that contraption was he was measuring voltages with. He even had a scope in the background during the video. I'm wondering why he's not using that since it would display the back-EMF from the injector coils much more precisely.
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ionbeam
2 FUN
The guy is teaching the general public. You can use a scope, I can use a scope, I'm willing to bet most people can't read a scope even if it was setup for them. You may have access to a scope, I have access to a scope, I'm willing to bet most people don't have access to a scope. OOOHHHH, flashing lights, LEDs that move up and down with numbers next to the LED segments -- most people can read the numbers. +1 to the scope though.
Looking at the + battery terminal with the engine warmed up and idling . The scope is ground isolated to the bike, AC coupled, 5mS, 100mV. Does this mean much to non techies?
Ok, now lets try a data plotter, triggered on Ch 1 and plotting two probes --
FWIW
That training video's intended audience is Yamaha Certified Service Technicians (hoo-rah). I know it ended up on Yootoobe but it is clearly far more detailed than your typical show-me video. I would think the Yama-Techies are able to be trained on how to read a scope, no?
I also think that there is something wrong with the second scope trace capture photo. The ignition should happen before TDC on the compression stroke. It appears to be happening more than the 50% point between injections, which would put the ignition after TDC. I suspect that maybe the labels got reversed?
Then again, there seem to be 6 intervals in the "injection" waveform, and three in the "injection" waveform, which makes me suspect that they are reversed and it is from a 6 cylinder engine.
I also think that there is something wrong with the second scope trace capture photo. The ignition should happen before TDC on the compression stroke. It appears to be happening more than the 50% point between injections, which would put the ignition after TDC. I suspect that maybe the labels got reversed?
Then again, there seem to be 6 intervals in the "injection" waveform, and three in the "injection" waveform, which makes me suspect that they are reversed and it is from a 6 cylinder engine.
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