I just swapped heads and intake on my 87 IROC LG4, now has a 350 swapped in. While trying to clean up wiring I found a connector that I dont think was hooked up before. The connector looks just like the one that goes in the sensor in the passenger head (coolant fan control...I think) but this one is a single white wire that goes back to the EST on the driver's fire wall behind the relays.

I've search for an hour now and can't find the answer. The Haynes wiring diagram says Spark Timing Output but doesn't show where it goes or to what sensor.

Can someone please tell me where this is supposed to go.

Thanks
Tim

 

Check your knock sensor located just to the front of the starter.