1996 Ford Mustang O2 Sensor Codes

1996 FORD MUSTANG
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RACINJASON
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  • 1 POST
Whats up guys, I've got a 1996 Mustang GT with about 95,000 miles on it and the check engine light has been on for a few months now and i've finally had time to go and get it checked out and the codes are PO136 O2 sens. B1 S2 and PO156 O2 sens. B2 S2. So im assuming that it means Bank 1 Sensor 2 and Bank 2 Sensor 2. So my question is, Are these the Sensor After the catalytic converters or the ones closer to the exhaust manifolds. I just dont know what the B1S2 and the B2S2 mean.
May 5, 2006 at 7:47 AM
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PEPPERMRJ
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P0136 O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)
P0156 O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)

bank 1 sensor 2 is after the converter on the left side (left side while sitting in the car faceing forward)

bank 2 sensor 2 is the right side after the converter
but I seriously dout that both are bad at the same time

They are the rear sensors after the cat. It is odd that they both would fail if the engine is running well. Sounds more like a wiring proplem. Maybe the heater circuit or the control voltage supplied by the computer. Best to check that first or have it checked out

Most manufacturers recommend replacement of all 4 O2s @ 100,000 miles. The front 2 sensor are the ones that effect performance, emmisions and fuel economy. The 2 rears monitor the front 2 and the operation of the cats. It will not pass a smog test with the check engine light illuminated.

Good luck and let us know. :)
May 5, 2006 at 8:34 AM
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Suggested Repair

Confirm both codes refer to the rear oxygen sensors after the catalytic converters. Because both failing together is unlikely, check the wiring, heater circuits, and computer-supplied control voltage before replacing the sensors.

Conversation Summary

A 1996 Ford Mustang GT with about 95,000 miles has codes P0136 and P0156 for bank 1 sensor 2 and bank 2 sensor 2. The expert explains these are the rear sensors after the converters, on the left and right sides respectively, and says simultaneous failure is unlikely. They recommend checking wiring, heater circuits, or computer control voltage first, noting the rear sensors monitor the front sensors and catalytic converters and that the illuminated check-engine light will prevent passing a smog test.

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