GM Celebrity/Century/Ciera/6000 1982-1996 Repair Guide

Pulse Air Injection (PULSAIR)


All engines use the Pulsair air injection system, which uses exhaust system air pulses to siphon fresh air into the exhaust manifold. The injected air supports continued combustion of the hot exhaust gases in the exhaust manifold, reducing exhaust emissions. A secondary purpose of the Pulsair system is to introduce more oxygen into the exhaust system upstream of the catalytic converter, to supply the converter with the oxygen required for the oxidation reaction.

Air is drawn into the Pulsair valve through a hose connected to the air cleaner. The air passes through a check valve (there is one check valve for each cylinder, all check valves are installed in the Pulsair valve), then through a manifold pipe to the exhaust manifold. All manifold pipes are the same length, to prevent uneven pulsation. The check valves open during pulses of negative exhaust back pressure, admitting air into the manifold pipe and the exhaust manifold. During pulses of positive exhaust back pressure, the check valves close, preventing backfiring into the Pulsair valve and air cleaner.

The Pulsair check valves, hoses and pipes should be checked occasionally for leaks, cracks, or breaks.


  1. Remove the air cleaner case. Disconnect the rubber hose(s) from the Pulsair valve(s).
  3. Disconnect the support bracket, if present. Some V6 engines have a Pulsair solenoid and bracket, which must be removed.
  5. Unscrew the attaching nuts and remove the Pulsair tubes from the exhaust manifold(s).

To install:
  1. First apply a light coat of clean oil to the ends of the Pulsair tubes.
  3. Install the tubes to the exhaust manifold(s), tightening the nuts to 10-13 ft. lbs. (14-18 Nm). Connect the support bracket and, if applicable, the solenoid and bracket. Connect the rubber hose(s) and install the air cleaner.