USS Backyard
07-18-2025, 01:12 PM
I have recently purchased a used MK3 with donor mustang gt drivetrain. Harness and everything looks factory. My question is, where would the spout connector be located if the factory harness is modified for the roadster? Or, if it is an older harness will it even have this connector? It runs rough when cold and i am trying to troubleshoot timing etc… If someone could point me in the right direction it would be very helpful.
gbranham
07-18-2025, 01:18 PM
The SPOUT (Spark Out) is on a short lead of wiring near the distributor on 1987-1993 Mustangs. Even on a dieted Mustang EEC-IV harness, the SPOUT is typically left in this location . I think they moved it to be near the passenger side where the inner wheel well meets the firewall, in the engine bay in 1994. The end of it is a small plastic connector that you remove while setting base timing, then replace when timing is set.
Do you have an old EEC-IV code reader? If not, they are readily available on Amazon, or I even have one I'd be happy to loan you. It might help you diagnose your cold engine stumbles. Maybe check your IAC for proper operation. The solenoid can stick and cause some bad behavior on a cold engine. Easy to test it by taking it off the car (assuming you still have it), and put a 9V battery across it's terminals with two short pieces of wire. If you hear it click, you're good. If not, take it apart and clean it up, reassemble, and try again. Also, depending on how the emissions system was removed/eliminated/dieted, you may have a vacuum leak or failed solenoid in the emissions system. Would be good to familiarize yourself with that system for the year Mustang harness you have.
Greg