R3X072

I am in the process of wiring up a '93 5.0 in a '85 Maxda RX7. I have figured most of it out with the help of fordfuelinjection.com as well as some other sites; however, I am stumped with these two. They are on the drivers side of the engine bay, and are close to the coil. The plug to the left has one large gauge wire, black/white coming out (it splits into 3 wires of the same color about 6 or 8 inches back). The one on the right has two wires, one black/white, the other black/yellow.

Can anyone give me an idea what these go to? I have a feeling the one on the left goes to ground, but don't want to do anything without being sure!

Thanks for any help you can send my way!

aleXander2648

Good question. I'll look under my hood and see what they go to not ringing a bell tho. I bet your car is gonna be light, somewhere around 2200-2400! thats a good thing

R3X072

I really appreciate it. Any direction at this point is welcome. It is one of the few things keeping me from firing it up...I think!

mattdel

The single on the left looks like it would be a coolant temp sensor plug, for the gauge. The one on the right looks like an O2 harness.

bear in mind this is simply what they look like compared to other harnesses. I have no direct knowledge at this point because I don't have a stang anymore.

I'll take a peek through Alldata's connector views and see if I can figure it out.

mattdel

OK. Here we go.
The plug to the left, that has a Black/White wire that splits into 3, is this circuit. Down on the bottom, at splice #122 is the split, and connects to connector C118, which is described as "Top RH Rear of engine, on rear of Intake Manifold"



C118


More to come...

mattdel

I can't find any info on the other plug, with the 2 black wires. It's not listed in any diagrams.

The connector is the exact shape of the intake air temp sensor, but the wire colors are different.

JD1969

I just went out and looked on my car. The one on the left is a ground, do you have the other side of the connector? It should have a ground loop for a bolt to go through. As for the other one, I could not find it, but all my wires are hidden, clamped and wire tired out of sight. I can tell it is not the O2 sensor, the wires are not the right color and the plug does not look to be the right shape. Maybe get us a better pic that shows the inside of the connector and the two wirs coming out if it.

R3X072

I actually did find the plug for that ground. I had thrown the battery harness off to the side, it was on there. It seems as though everything is working, with the exception of the fuel pump. I can't seem to get the relay for the fuel pump to fire up for some reason.

Can you all take a look at the diagram on this page, just over half way down?
http://fordfuelinjection.com/?p=6

On the fuel injection harness power circuit, the lead from B+ that is fused, does anyone know where that wire is? Thanks again for your help!

Oh, will get a picture up of that other plug asap.

R3X072

I got it. There were two fused wires coming out of the harness beside the wires that needed to be grounded, one was the power wire for the fuel pump, the other for the Mass Air/O2 sensor relay.

I got it started tonight briefly. Now time to go through and clean everything up with some reliable connectors.

R3X072

Well, I thought I had it. When I start it, it runs great for a few seconds, then dies. I am 99% sure it is a lack of fuel pressure. When I put a voltmeter on the leads going to the fuel pump, turn the ignition to the acc position without turning the car on, the fuel pump lead reads 12 volts, then jumps down to 6 volts after a few seconds. I am assuming this is my culprit. Any ideas what I have done here?