Author Topic: 3-wire Heated O2 Sensor  (Read 7052 times)

Offline ehjorten

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3-wire Heated O2 Sensor
« on: February 27, 2015, 01:47:03 pm »
So what 3-wire O2 Sensor should I be picking up to convert my '91 TBI 454 to a Heated O2 Sensor?  What application can I tell the parts clerk, so that I get the one that fits?
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6

Offline LTZ C20

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Re: 3-wire Heated O2 Sensor
« Reply #1 on: February 27, 2015, 02:28:17 pm »
Is the truck currently set up to use a heated sensor? If the wiring is not present and the ECM isn't setup internally for it then it's not going to work.

What are you trying to achieve by changing the sensor.
LTZ Cheyenne C20

Offline ehjorten

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Re: 3-wire Heated O2 Sensor
« Reply #2 on: March 02, 2015, 09:09:08 am »
You can add a 3-wire O2 sensor to a truck with a 1-wire O2 sensor very easily...you just need to tap into switched+ and a ground- for the heater element.

I have headers and 3" exhaust.  The heated O2 sensor is supposed to help keep the system in closed-loop mode under idle and when at light cruise on the freeway.  The 4-wire O2 sensors are the ones that have a seperate ground for the heater element that is controlled by the computer.
« Last Edit: March 02, 2015, 09:25:26 am by ehjorten »
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6

Offline LTZ C20

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Re: 3-wire Heated O2 Sensor
« Reply #3 on: March 02, 2015, 09:55:09 am »
Sounds good to me. I have headers, 2.5 inch exhuast and the truck is TBI with a 4 wire O2.
I wasn't sure if you had something planned or just were taking a shot in the dark on an idea. You got it covered tho, carry on.

Btw, I don't have any part numbers.
LTZ Cheyenne C20

Offline ehjorten

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Re: 3-wire Heated O2 Sensor
« Reply #4 on: March 03, 2015, 09:05:17 am »
Found this on 3rdGen: http://sethirdgen.org/HO2S.htm
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6