There is more than one O2 sensor in that vehicle and they are all threaded into the exhaust at various points.
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on the top of the intake
That should be the sensor located after the catalytic converter.
Inside the distributor.
A replacement heater core would cost aprox $35.
what is the wiring diagram for the o2 sensor on 2000 s10 blazer. it has 4 wires. what what do they all do /
$400 to $600 depending if it has ac or not.
extended pickup
It's in the intake air tube, near the air filter.
The ECM controls the timing with information sent to it from sensors such as the crank sensor and the knock sensor.
left side back of engine by dist.
Locate the crank sensor behind the vibration damper (crankshaft pulley). Unplug the wire harness connected to it. Remove the small bolt holding the sensor in place. Remove the sensor.