i had the same problem a while back. turned out to be cracked hoses under the manifold. replqced those and everything was fine. u could also check the pump using inpa. go to the engine section amd activate the pump. it pumps air thru a hose connected directly to the air filter. u cam.activate the pump, disconmect the hose and check if its pumpimg air. the secondary air system only has a few parts so it should be easy to check. also, did u check ur valves? maybe they're not closing properly?
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