I am pulling a code #29 from my scanmaster. It just started this morning on the way to class. It does the classic fan turn on when the light is on but when it turns off the fans turn off. The light comes on and off but the scanmaster holds a steady code 29. What could this be? This is from a 94 trans am LT1 A4.

 

29 = Secondary Air Injection (AIR) pump circuit

Found the code but now what to do about it?

 

bump

 

Check the fuse for the AIR pump. In OBD-I, a blown fuse or relay is the only thing that will set the code. If you replace the fuse, and it continues to blow, just unplug the AIR pump connector, replace the fuse and the SES light will not return. There is a factory recall on the 95 and newer AIR pumps.

 

Sure enough it was a blown fuse. I replaced it and haven't seen the SES light come back on but the scanmaster still has the code pulled up.

 

Once the code is set and "active" it remains stored in the PCM, even though you have fixed the problem. Eventually, after a defined number of "drive cycles" without the problem coming back, the PCM will self-clear the stored code. You can clear the code by pulling the "PCM BAT" fuse for 30 seconds. It's in the fuse box on the end of the dash.

Also check the fuse again... might have blown if the pump is siezed.