modifying a 5.0 mustang maf efi harness for ….pdf

Modifying a Mustang MAF EFI Harness for Standalone Operation in Another Vehicle Starting Point: A used harness can be sourced from any equipped Mustang with Mass Air Flow (MAF). MAF was first introduced in 1988 on Mustangs originally sold in California. Starting in 1989, all Mustangs were MAF. Fuel injected Mustangs sold prior to these years were equipped with Speed Density EFI. These harnesses can be used, but will require modification for use with MAF. Speed Density harnesses will require the addition of the MAF sensor connector, a Vehicle Speed Sensor (for manual transmission EECs), and the removal and relocation of several pins in the 60 pin EEC connector. Harnesses from 1994 -95 Mustangs may also be used, but are less po pular and not covered by these directions. Wiring colors changed a little bit over the years, so your individual harness may vary slightly from the descriptions listed below. The function of the individual connectors is the same and the sensors are the s ame –the change in wiring colors doesn’t matter at all. An easy way to tell if your harness if from a 1994 -95 model is the absence of the 2 large black & white 10 pin connectors that connect the engine harness to the main harness. 1994 -95 models used a single large connector. A typical early ‘90s Mustang EFI harness: EEC Choices You can use virtually any EEC -IV EEC that was used in a EFI Mustang. The EEC program can be found on a sticker on the EEC where the 60 pin connector plugs in. The most popular program codes used are A9L (for manual transmissions) and A9P (for automatic transmissions). There are differing opinions on whether or not you can use an A9L with an automatic and an A9P with a manual transmission, but I’ve heard that eithe r one will work with either type of transmission. The EEC does not control the transmission and it really doesn’t care what type of transmission is behind the engine. There is one very