wirteing issues , please help

[jhr351]

rescently got a new main engine wireing harness for my 88 gt , the harness is for maf , which i have converted to , the harness is in an connected , except for one connection which isnt on the harness , on the original harness it would have been a grey 8 pin connector , i was woundering what this was for on the stock harness , it is located on the drivers side near the break booster

 

[jrichker]

If it looks like this, it is the computer diagnostic connector used to dump the codes stored in the computer

 

[jhr351]

no it was the two next to that the harness i got only had one connector , and the stock 88 harness has two

 

[strtrcr50]

Sounds like you got a 90+ wiring harness. Only the 89 is a direct plug and play. The 90 plus has a different dash harness and only has one hookup near the driver's side firewall. I believe the ford racing harness comes with only one and I believe they tell you how to rewire it. I'll dig around and see if I can find it. Here's a chart for compatibility.

1987-1988 Speed Density. All the speed density engine harnesses are interchangeable. Ford used a different computer in 86, but the engine harness is the same. The dash harness in the 86 is specific to that year car and will not work in the 87-93.
1989 Mass Air and No Air Bag. One year only harness. Only car with mass air and no air bag. The dash harness is the same from 87-89 on all models, but the engine harness is specific to the 89. The 89 harness can be used in place of the stock 87-88 harness for anyone looking to do a mass air conversion.
1990-1992.5 Mass Air with Air Bag. Fuel pump relay is under the drivers seat. The change here was made sometime in 92. All the dash harnesses for all models from 90-93 are interchangeable.
1992.5-1993 Mass Air with Air Bag. Fuel pump relay is in the engine compartment. M12071C302 is this style engine harness. All the dash harnesses for all models from 90-93 are interchangeable.
1994-1995 All the engine harnesses from the 94-95 V8 cars are interchangeable. All the dash harnesses from the 94-95 cars are interchangeable.

 

[jhr351]

thanks for the info , , found out that i only need three of the wires in the new harness , i need two crank only source 12v , an one crank and run 12v power source , i just have to find those , an hopefully this fixes the other problems i was haveing with this car, thanks for the help:SNSign:

 

[BK_CAULEY]

i heard you need a wiring harness ofr a 1990. well i need one for a 1991+. wanna trade. pm me if you do.

 

[samstigg]

Sounds like you got a 90+ wiring harness. Only the 89 is a direct plug and play. The 90 plus has a different dash harness and only has one hookup near the driver's side firewall. I believe the ford racing harness comes with only one and I believe they tell you how to rewire it. I'll dig around and see if I can find it. Here's a chart for compatibility.

1987-1988 Speed Density. All the speed density engine harnesses are interchangeable. Ford used a different computer in 86, but the engine harness is the same. The dash harness in the 86 is specific to that year car and will not work in the 87-93.
1989 Mass Air and No Air Bag. One year only harness. Only car with mass air and no air bag. The dash harness is the same from 87-89 on all models, but the engine harness is specific to the 89. The 89 harness can be used in place of the stock 87-88 harness for anyone looking to do a mass air conversion.
1990-1992.5 Mass Air with Air Bag. Fuel pump relay is under the drivers seat. The change here was made sometime in 92. All the dash harnesses for all models from 90-93 are interchangeable.
1992.5-1993 Mass Air with Air Bag. Fuel pump relay is in the engine compartment. M12071C302 is this style engine harness. All the dash harnesses for all models from 90-93 are interchangeable.
1994-1995 All the engine harnesses from the 94-95 V8 cars are interchangeable. All the dash harnesses from the 94-95 cars are interchangeable.

Ok Sorry to barg in on this thread but I have been searching the web for just this kind of info..here is my problem.

I am in the process of a 2.3 to 5.0 conversion on my 92' 2.3 LX. I have a 90' 5.0 LX donor car. We swapped out the motor, ECM, Engine harness and all suspension, fuel and brake components. I have just recently realized that my 92' is actually a 92.5 and thus had the fuel relay in the engine bay (ahich was removed with the 2.3 harness. So I have gutted the interior and am now replacing the body harness with the 90' harness which has the fuel relay attached to mount under the drivers seat. Here is my question; I have heard so many times that a dash harness is a dash harness, that the 2.3 dash harness would work fine and does not need replaced. Will my 92.5' 2.3 dash harness work with the 90' engine and body harness or should I tear out the dash and install the 90' dash harness as well?????

By the way I am new to this site and greatly appreciate any and all help you can provide.