what is the secondary air injection pump for on a 2000 gmc jimmy sle 4.3

the secondary air pump only is commanded to run when the engine is cold to pump air into the exhaust manifold to complete burning in the exhaust. there is the motor and the check valve in the system and they need to be checked for commands to determine the issue. once again, a 410 code only says there is a problem, it does not say the motor is bad. it is located under the right front of the envoy at the bottom. it is a round motor with a couple of 5/8 hoses and an electrical connector. Roy

This A.I.R. pump lives down on the right lower side of the engine compartment, most lickely mounted on a engine bracket. It is an electric motor controled by your engine computer, it also has four fuses, two grounds and a relay involved. The computer grounds the relay when it wants the A.I.R. pump to run. The Question is not where the pump runs to and from but is it operating or not? most lickely this is an electrical problem or a bad A.I.R. pump motor. If you have some knowledge of how to check for power and ground, and either a volt meter or test light that is safe to use on computer circuts, you can check the fuses, grounds, and if the computer has energized the relay from the A.I.R. pump plug end. But if you dont have these tools or knowledge, this is a job to take to a pro, someone you trust ! You will be paying a dignostic fee, the labor to replace the pump if needed is close to one hour, the part cost around $200.00 some more, not mutch less. I hope this helps you. Tom