I rebuilt my engine for my e30 s50 m3 and have a question on the knock sensors wiring. I'm trying to connect the knock sensors but I can't tell which connector from the wiring harness is for 1-3 and which is for 4-6. I peeled the rubber boot and noticed the wires are the same color for both, but do see that one has a round blue ribbon and the other has a yellow ribbon. The Bentley doesn't show these, it just shows the wire color which both are the same. I know I can do a continuity test from the main ecu harness to either of the two sensor harness. But if any one knows just by the ribbons it will save me a lot of time. Thanks