Richter12x2

Pretty sure I know the answer to this, but thought I'd run it by the experts since I'm still new to the cars.

As I'm rewiring the engine harness, I started with the fuel injectors and some new connectors. As I'm running them, I find one factory connector with brown and red reversed. I went ahead and mimicked their wiring with my new wires, thinking maybe it was for the second phase of injection, but after getting all the way to the end, it's the only one with reversed wires. The connector is stock, and I didn't make a mistake (because I haven't cut anything on the original harness yet) so this connector was out of phase from the factory.

Is there any reason why one injector would/should be out of phase on an '85 5.0?

sidehatch

When i did my ends on my 1989 those colors were switched multiple times i left it the way they had it.

davek9

Try this Thread:
Rennlist Discussion Forums > Water Cooled Technical Discussion Areas > 928 Forum
The Official Fuel Injector Thread

Oh.. they should be the same, one is hot ~ +12v dc and the other is switched ground, by the computer, They all fire at the same time.

sidehatch

Im not sure if having those wires switched is going to matter,mabe someone else on here knows the answer,but on mine there was mabe 2 or 3 that were switched.If they werent firing rite i think i would have a green light on the computer.

blown 87

It should not matter what the polarity is, it is just a simple coil.

ZEUS+

The lights are on the ignition monitoring relay. A green light would indicate ignition circuit 2 is shut down and cylinders 2,3,5, 8 injectors will not pulse.

Richter12x2

Makes sense. I thought I saw in the wiring diagram that there were two sets of four (four fire at a time) with two different wiring colors between the sets, but when I rang them out to make sure the wires went where they were supposed to, it seemed like they all went to the same two pins (1 hot and 1 ground). I didn't pay majorly close attention though, since I wasn't terminating the plug end, just measuring for length.

Richter12x2

I guess you're right, but try telling that to a car audio guy!

davek9

On your year 85 they are all connected to the same circuit, all 8 fire at once.

On the later years starting around 89(?) there is a Cat protection circuit (and relay with a red and green led) that will cut the fuel to four of the cylinders by disconnecting four fuel injectors.
The four cylinders are either 1, 4 , 6, 7 or 2, 3, 5, 8 (follow the ignition wires
Temp change sensors in the head trigger the relay to prevent raw gas from starting a Cat fire.

85 – 88(?) do not have this protection, just put in a X pipe, remove the CAT’s and frogetaboutit

docmirror

Actually, there is a phase relationship in audio that is quite apparent for polarity. It is beyond the scope of this subject, but it can make a difference in audio circuits. In this case(injectors), polarity isn't a factor.