1981 Toyota pickup without oxygen sensor?

1981 TOYOTA PICKUP
4 CYL • 2WD • MANUAL
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2OUTSEIDERS
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I just tried to replace the oxygen sensor in my 81 toyota pickup SR5 but couldn't find it. It looks like the intake manifold has a blank spot right where the sensor should go. Does anyone know what is going on? Did someone put an aftermarket manifold on to eliminate the o2 sensor? I looked around and could not find the wiring harness for the sensor. Did 1981 toyota's have o2 sensors at all? Any info would be appreciated.
Lonnie
Jan 23, 2011 at 4:36 PM
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WRENCHTECH
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Oxygen sensors don't go in the intake manifold. the go in either the exhaust manifold or exhaust pipe.
Jan 23, 2011 at 4:46 PM
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RASMATAZ
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O2 sensor Mounted On Exhaust Manifold Applicable to: 1981-83 Models


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Jan 23, 2011 at 4:48 PM
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2OUTSEIDERS
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Sorry, I meant exhaust manifold. Here is a picture
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Jan 23, 2011 at 5:09 PM
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2OUTSEIDERS
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I'm looking at the diagram and I just don't know where or what it bolts into. Should go into the exhaust manifold but there is just a blank spot there.
Jan 23, 2011 at 5:13 PM
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WRENCHTECH
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Do you have a check engine light? If you have a non-electronic carb, it may not have one.
Jan 23, 2011 at 5:17 PM
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No check engine light that I know of. Carburetor only has a couple of wires going to it and they are for the fuel cut solenoid and the choke. 3 wires total. So it looks kind of like the engine doesn't have an oxygen sensor. Can anyone explain why I might be getting only 18 mpg out of this little 4 cyl? I figured I would be getting at least 25.
Jan 23, 2011 at 5:28 PM
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WRENCHTECH
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It's 30 years old and carburetors were never very efficient. I don't know why your expectations are so high.
Jan 23, 2011 at 5:31 PM
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RASMATAZ
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There's a lot of contributing factors within the vehicle subsystems to mess with fuel economy such as the following-Badly needed tune-up and adjustments, carbueration problem, slipping clutch, brake dragging,wheel alignment and tires/suspension problem and the list goes on in my checklist
Jan 23, 2011 at 5:41 PM
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2OUTSEIDERS
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Thanks for your input guys. You've helped a lot. I was just baffled that the truck didn't have an o2 sensor. Again, thanks for the quick replies
Jan 23, 2011 at 5:58 PM
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