Oxy sensor plastic connector gone/identify unmarked wires

Tiny
WETMOREDALE
  • MEMBER
  • 1986 FORD BRONCO
  • 150,000 MILES
1986 Bronco II, 2.9 V6, EFI, 4WD/Man Trans. Found oxy sensor plastic connector had melted in contact with exhaust. New sensor(heated type) has black/ground wire & 2 white wires. Ford harness has black & 2 color coded. I could hard-wire new connector with waterproof splices. How do I tell which white wire is power in, and which one is output to computer?
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Monday, July 29th, 2013 AT 1:13 AM

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Tiny
CJ MEDEVAC
  • EXPERT
MAYBE THERE IS AN EZier WAY

THE OUTPUT WILL "PUT OUT" A MILLIVOLT READING WHEN THE VEHICLE IS AT OPERATING TEMPERATURE

YOU CAN USE A VOLTMETER SET ON "MILLIVOLTS". RED LEAD TO "TEST WIRE". BLACK LEAD GROUNDED TO VEHICLE GROUND

NORMALLY IF YOU "TAP INTO" AN O2 SENSOR OUTPUT WIRE WHEN IT IS HOOKED UP 100% AND ALL IS OPERATING CORRECTLY. THE COMPUTER WILL SORTA "HOLD" OR "BOUNCE AROUND" A.450 MILLIVOLT READING. THAT IS, THE O2 SENSOR IS TELLING THE COMPUTER WHAT THE OXYGEN CONTENT IS. THE COMPUTER IS ADJUSTING THE FUEL TO MAINTAIN THE.450 MILLIVOLTS

"PERFECT BURN" OR "THEREABOUTS" OR WHAT IS CALLED "STOICH" IS A 14.7 PARTS AIR/ 1 PART FUEL.A COMPUTER CAN KEEP THAT "MIX" CLOSE. SO FOR LACK OF A BETTER WAY OF EXPLAINING IN MY EXAMPLE, .450 MILLIVOLTS = PERFECT BURN

ANYTHING GREATER IS "RICH". ANYTHING LOWER IS "LEAN"

NOW. WITH WHAT YOU ARE DOIN'. THE O2 IS NOT GONNA TELL THE COMPUTER ANYTHING YET. TILL YOU GET THE CORRECT WIRE FIGGERED OUT

I DON'T KNOW WHAT YOUR READING WILL BE WHILE SEARCHING. MOST LIKELY "RICH"

MY 1977 CJ 5 HAS AN O2 SENSOR. BUT NO COMPUTER. IT IS INSTALLED AT THE END OF MY HEADER

I INSTALLED AN AIR/ FUEL RATIO GAUGE ON MY STEERING COLUMN. IT IS THERE TO AID ME IN SELECTING THE CORRECT JETS FOR MY HOLLEY CARBURETOR.A CARB CANNOT HOLD THE "PERFECT BURN" AS IN A NEWER CAR. BUT WE CAN DO, ALL WE "CAN", TO GET IT AS CLOSE AS WE CAN!

THE "GAUGE" IS A SERIES OF LEDs, RED (LEAN), YELLOW (STOICH), AND GREEN (RICH). THE LIGHTS TAKE THE PLACE OF THE VOLTMETER. THE GAUGE IS A LOT EZier TO COMPREHEND, THAN THE CONSTANT CHANGING NUMBERS ON THE VOLTMETER

MY MPGs ROSE FROM 15 WITH THE STOCK CARB, TO 18 USING THIS METHOD AND THE HOLLEY

THE MEDIC
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Friday, August 2nd, 2013 AT 12:15 PM

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