Electrical 1988 GT T-5 MAF conversion


New Member
Oct 6, 2020
St. Louis
Hello ladies and gents. New member to the forum here. Long story short. Have an 88 GT t5 that was carb swapped. (No harness, ECM in the car anymore). Rebuilding the motor and going to MAF.
From researching over the past couple months, I’ve finally located a complete 89 Harness to direct swap to MAF including O2 and injector harnesses.

I have both a A9L and A9P available to use for the car. Want to run the A9L because just makes sense being a 5speed and have it.

Going through the harness now and double checking for any knicks and fixing accordingly before installing. At the O2 harness and have a question. Gentleman I purchased the harness from stated it was from a 89 5.0 t-5. Plug says different occurring to the P/Y jumper. I’ve also located 2 other Y splices and not sure if these are that way from the factory. Also on the passenger side lead for the sensor, the W/P wire from the plug is not connected to anything and curious what is for or is this thing jacked up? Want to make sure all my ducks are in a row before getting the harness in, hooked up when motors done and fire it up I’m not going to fry the A9L.

Pics attached and Appreciate any insight. Thanks.


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