Under the battery, all the way down under the car. You'll have to remove the plastic curtain to access it.
The 1985 Ford Ranger smog pump is located on the firewall in the engine compartment. The smog pump will be on the drivers side of the firewall.
another name is smog pump.this could cause light to come on.
http://wiki.answers.com/Q/Where_is_the_smog_pump_0n_a_2000_chevy"
It is located right below the alternator.
pumps smog
The smog pump is also known as an air pump. It's only purpose is to blow more air into the exhaust system to help burn up unused fuel and carbon monoxide in the exhaust.
Smog pumps have not been used for at least 20 years, as far I can recall. My 2000 Malibu does not have one. Better engine controls through electronics have allowed for this.
driverside wheel well in behind the front bumper
The 2001 Oldsmobile Aurora smog pump can be found on the left-hand side of the engine. The smog pump will be near the exhaust manifold.
Go to Autozone and get an 88.2-inch 6-rib serpentine belt. This will effectively bypass the smog pump and keep all other accessories operational.
93.5 inches for the bypass
loosen altinator, loosen smog pump, take smog pump belt loose, then take altinator belt over smog pump belt and over fan