Engine Harness Nightmare From Hell! Help me ID some things? Pics

Blau · Dec 1, 2013

Hello! Let me preface this by saying that my car is a 2000 with a '94 5.0 swapped in. The previous owner of my 'stang took the O2 sensors out.. don't ask me why. I found some, put them in, but couldn't find the O2 sensor harness under my car. Figured I don't have one, but wanted to make sure by looking for it in the engine bay. So I took a look at these diagrams here -

40 is where the O2 harness should plug in, right next to 24, which is the MAF sensor plug, right? Under my hood is a totally different story... a nightmare. Can you guys help me decipher this crap-work? I'm having a hard time finding any definitive information on this on the web. My MAF is off, and sitting on top of my throttle body off screen in the first picture.

According to the diagram, 24, 40, 33, and 32 should all connect at the question mark, where I have a plug instead, and a wire that runs to A. The O2 harness should plug in right here... What is A?
Green arrow to the next picture.

The wire continues down until it meets with a much thicker bundle that runs into my wheel well, and also connects to B. and C. What are they?
Green arrow to next picture.

The wire continues toward the front of the car, splits apart into these plugs, then recombines... Anyone have any idea what's going on there?
Green arrow to next picture.

The bundle then runs to my headlights in one direction, and then across the front of the car in the other, where these two plugs come out of it. Is D the O2 sensor wire harness connector? Anyone know what E is?
Green arrow back to the next picture.

The bundle that ran into the wheel well in picture 2 comes out closer to the front of the car, where plug G comes out. Anyone know what this is? Farther down the line, the bundle connects to F, and then runs across the front of the car.

At the same time, I have these mystery plugs coming out of the wheel well.
All of these plugs are part of the same large bundle in one way or another... hm.
I appreciate any info/help you guys can offer! I figured I should try and find out what all this jazz is while I'm looking for the O2 harness plug. Thanks so much.

95opal · Dec 1, 2013

First pic (a) is the incoming air temp.

Second pic (b) spout connector for setting timing. (c) TFI module

Last pic is vacuum for emissions crap

Your o2 harness will be down in the the bell housing area usually push pinned onto the k-member

rz5.0 · Dec 1, 2013

O2 harness comess under the car around the pan if I remember right. .

Paul · Dec 1, 2013

A = Intake Air Temperature Sensor
B = PIP Spout to fix timing advance when setting ignition timing on your car (this is what you pull, set car to 10* timing, then put back in)
C = TFI module
D, E, F = I think that's ABS connectors? I can't remember off the top of my head. If I had the car in front of me I could figure it out.
G = I can't remember, sorry.
???? = Vacuum lines for emissions control

Paul.

rz5.0 · Dec 1, 2013

G: Goes on the hard line coming off the ac condernsor passenger side.. I think it's a green plug. .

rz5.0 · Dec 1, 2013

D, E : connect the driver side harness with the the ccrm ... I'll double check tomorrow morning when I get home. .

kb1982 · Dec 1, 2013

You have just giving me a happy feeling. I now know im not alone dealing with previous owners wiring harness woes. Connector D is your main 02 sensor harness connector. Just a question, how do your fans on your car operate. Are they wired to be constantly on? Im thinking about getting me another harness that hasn't been hacked up, busting it apart, and deleting all the connectors that i wont be using. The connector that you are holding in your last picture, the 90 degree miniature spark plug looks exactly like what the oil pressure and coolant temp guage sending unit use. They have a little stud that it pushes onto.

kb1982 · Dec 1, 2013

kb1982 said:
You have just giving me a happy feeling. I now know im not alone dealing with previous owners wiring harness woes. Connector D is your main 02 sensor harness connector. Just a question, how do your fans on your car operate. Are they wired to be constantly on? Im thinking about getting me another harness that hasn't been hacked up, busting it apart, and deleting all the connectors that i wont be using. The connector that you are holding in your last picture, the 90 degree miniature spark plug looks exactly like what the oil pressure and coolant temp guage sending unit use. They have a little stud that it pushes onto.

Nix the D as your O2 harness. Look up underneath the intake manifold for it. That is where mine is shoved to. If not there, the connector should be somewhere around the bellhousing of the tranny. I bet the previous owner had wideband o2 sensors wired up and then took them out. The widebands utilize their own controllers to heat them up, thus only one wire needs to be hooked up per controller which is the output on the wideband controllers to the ecm

rz5.0 · Dec 1, 2013

D is not the 02 harnesses. That supplies 12v to the fans that go the ccrm..

rz5.0 · Dec 1, 2013

http://www.sn95forums.com/showthread.php?53598-fan-trouble/page2
Old post of mine. Second page forward the bottom you will see a pic of D and if you look closer to the Corner you will see the green plug were g plugs into. .

Blau · Dec 8, 2013

Thanks a million guys! I took another look under the car.. and lo and behold... they were there. Can't believe I didn't find 'em earlier. Problem is that they are about 3 feet upstream from my O2 plugs - one is even about a foot above my long tube collectors. Suppose I should buy a couple sets of extensions? They don't seem to have any slack.

Does anyone know what that odd smaller plug is coming off of the driver side O2 harness? Sorry for the odd orientation of the pictures.