IM not sure what the plug is that you undo to set the timing. But What i have found currently is that I had a code 42 while it was connected. I went to reset my timing and I disconnected it. The code 42 went away and the timing still advances like it should under throttle?

So I am confused anyone have any ideas what would be causing the code 42 in between that cable and the ecm?

I was also getting horrible fuel mileage when it was connected, i have a 2 hour drive tonight and I will update on my fuel mileage while driving it disconnected.

 

The EST/BYPASS connector is under the hood on the passenger side. Is this the '91 in your mini-sig?

It is a single wire (TAN/BLK) with an connector inline. It is located in the area of the firewall where the big HVAC box is. It exits the harness, has the connector, then reenters the harness.

RBob.

 

 

Found out that when i disconnect the est wire (white wire from the distributor to the ecm. I could get the code 42 to go away. But it would come back in 30 minutes to an hour. Now I'm not sure why disconnecting that wire would remove the code even for a little while. Especially since it has a brand new coil pack and distributor. I'm thinking it could be a loose connection to the ecm, but that doesn't explain why when it was disconnected the code went away. Idk maybe it's just a bad ecm.

Anyone got any ideas. This is literally the last problem I have with the car.