So I know on later MK4 ECU's they output their RPM signal on CAN bus but also on T121/37. For the square wave output, does anyone know how many pulse per revolution there are? I've looked in the FR and it gives example for 3 and 4 cylinder engines. If I'm reading it correctly it gives 2 pulses per revolution for 4 cylinder and 3 for 3 cylinder. Going off that I would be inclined to say that it generates 3 pulses per revolution for 6 cylinder but if someone could confirm that would great
so far as I know its same as a VR6, that is 3 pulses per full engine rotation rather than 2 pulses like on a 4 cylinder engine. I've seen many people use VR6 clocks with R32 engines to get the right rev counter calibration but one guy was adamant the output was same as a 4 cylinder...
Ahh that's what I thought. The reason I can see that is climatronic uses those pules to know engine speed. But there isn't a coding option to specify whether you have a 4 or 6 cylinder car
Yeah there is that, but my thoughts were maybe the difference is only slight so VW weren't worried about it? The other thing is there are different codings for 4 and 6 cylinder engines on the early non-canbus cluster so I assumed that was for setting the rev counter calibration. I've not managed to test this myself either way so be interesting to see what you find
Ahh that is possible. I don't have a V6 but, if I can be bothered, I'll drag the rain tray off the V5 and probe the ECU output to see what it does. I've asked on NefMoto about what I found in the FR, i.e. why it shows 3 and 4 cylinder outputs but doesn't even allude to other cylinder configs
