Quote:
Originally Posted by dcb
It is something DieselJohn had mentioned a while ago. The steel fuel lines actually expand during the injection on the old diesels, and it can be sensed with a clamp on sensor that came with some tachometers.
Edit: found a reference, don't know what the signal looks like though.
ONO SOKKI - GE-1200 Diesel Engine Tachometer |
Those steel-tubing fuel lines expand!? I suppose that's possible, but it sure wouldn't be by much.
Oh - I read the reference. The sensors measure vibration of the fuel line, not expansion. That seems more doable. You'd have a lot of work to do since it counts vibration events - not length of the events. Its response time appears to be 0.5 seconds, which is way slower than you would need. Still, you might be able to use some sort of piezo-electric sensor with different electronics. You could also use a microphone to detect the sound of the injector firing (which in its own way is detecting vibration). This is getting so complicated it might be easier to just buy a new car with OBDII.