so red and blue wire is only wire hooked to solenoid crank only? and pin 46 grounded at all times being its a swap?
The red/blue wire feeds power the starter solenoid and the TFI module. It is energized when the key is in the Start position to crank the car and tell the TFI to provide more dwell for increased spark for cranking.
The pin 46 is signal ground for all the engine mounted sensors and the MAP/Baro sensor. It is always grounded no matter what position the ignition switch is in.
O2 Sensor harness interchange and modification
Originally Posted by 302EFI
Revised 16-Oct-2011 to add O2 sensor harness warnings
The wires for the 02's and low oil did not change throughout the years, they are all in the same place.
The main ones you need to worry about are (on the harness end (ECU) that plugs into the 02 plug) is:
\- 1. Lightblue / yellow
- 2. White / Purple
- 3. Purple / Yellow
The White/Purple & Purple/Yellow gets looped for a automatic ECU
The Purple/Yellow & Lightblue/Yellow for a manual ECU
See
http://forums.corral.net/forums/gen...manual-auto-differences-year-differences.html for more O2 sensor wiring harness info
Basic premise to use with transmission swaps:
Only run a 5 speed trans O2 harness with an A9L. Do not run an Auto O2 sensor harness with an A9L. Doing so will damage the computer’s internal signal ground.
Only run an Auto trans O2 sensor harness with an A9P in a car that has an Auto trans. Using a 5 speed trans O2 sensor harness with an Auto trans will cause no crank problems.
See http://www.stangnet.com/mustang-forums/749974-computer-issue.html#post7490537 for Joel5.0’s fix to the computer internal signal ground.
90 model year harness only works with 90 model cars without inspection/rework.
The 4 cylinder O2 harness uses 4 wire O2 sensors. It probably won’t work correctly without modifying it.
If it is a 5 speed O2 sensor harness, it is usable without any modifications when you do a mass air conversion and use an A9L computer and 5 speed transmission.
