red/grey wire 94 exp

[smegun]

im trying to check wiring for cross talk before putting in top harness /top end

I had more than a few bad injectors looking at the bottom harness that leads to the engine fuse box there is a black and a grey bulk connector that connects to the top harness half .....no cross talk that i can gather from pins but I have the red/grey striped wire showing a buzz or continuity to the rest of the engine block! also with the orange wire and red ltblu wire ..... is it supposed to do that ?? the o2 sensors are not connected the entire top harness is out

if I connect the negative battery terminal to the positive battery lead there is no continuity only the engine block and various close ferrous parts

ive modified the pic

lattest mod I disconnected the pcm harness nice 10mm din there passenger foot jamm area and put the vehicle in reverse to take it out of park still with continuity from the red grey to orange and red lt blu and the engine block

 

[smegun]

an moderator at another well known explorer site states that this is a common wire to sensors and Its supposed to ground out

later I write that I guess the pcm knows how to adjust to an aftermarket … a debugger

anyone with a page of sensor values would be cool like my injectors at least most of them test out at 16.5 ohms +/_ .2 percent

 

[RonD]

Grey/red is the common ground wire for the sensors, called SIG RTN

Not seeing a Red/grey in engine wiring?

Yes, 16ohms is fine for Ford injectors, between 11 and 18ohms is spec

Just google sensor name and add "test"

Sensors rarely fail and are often replaced, lol

 

[smegun]

mostly a red wire with grey stripe like pin 1 on the bottom harness gang connector it is common with orange to o2 sensors and what appears to be a lite blue with red stripe that would be the { neutral park or clutch } in the skematic were it connected to ground is what I was trying to deduce imagining a sensor tweeked to ground



any difference I have two ump1 pcm one is from a limited on the schem it says all but limited ???

 

[RonD]

Very odd, all my work on engines I have found grey/red and all my diagrams show grey with red stripe as sensor ground, yes orange O2 wire is the sensor ground so connects to grey/red

 

[smegun]

isnt a very strong suit of mine no worries ive got the heads on now the rockers and top end my injectors have been the problem all this time evidently I just got too many frozen hoping its not the coils Im doing a pin out


UL isn't a very strong suit like the super beetle had a big gang connector in the back so vw repair shop could plug in and diagnose a common fault at least that should be the norm where companies are required to extend the requirement to find unequivocally a common problem