Codes PO 491 and PO 492 Secondary Air system
I've had the Check engine light on for the last 3-4 days and recently got the codes scanned at Schucks that say
PO491 Secondary Air Injection System Insuffiecient Flow (Bank 1)
PO492 Secondary Air Injection System Insufficient Flow (Bank 2)
I need help on trying to fix the problem myself before paying for a real mechanic. Any suggestions?
The car runs fine! Its a 2001 325xi wagon with about 34,000 miles.
I believe your seconday air injection pump has ..
gone bad. There was a post here a while ago with a picture of the air pump and in the pic the rivets that held it together had popped. The secondary air pump is located on the passenger side of the engine compartment just ahead of the strut tower - it is a round black can looking device that pumps air into the exhaust manifold for emissions purposes. It has a relay that engages it and valve of some sort where it pumps air into the exhaust manifold. Got this from the Bentley manual. Hope it helps DV
Re: I believe your seconday air injection pump has ..