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Old 01-25-2013, 01:03 PM
Ricardo567 Ricardo567 is offline
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Location: U.S
Join Date: Mar 2010
Posts: 34
Mein Auto: BMW 1994 325IC
Secondary Air Injection System

Originally Posted by Stephen Max View Post
The first two links are not applicable to your 545i. Unlike the 6 cylinder engines, the N62 SA system does not use vacuum operated check valves, and the fresh air is routed through the heads into the exhaust ports, not into the headers. The CEL is activated when the O2 sensors don't sense a lean shift due to fresh air entering the exhaust during SAP operation. This can be due to a cracked y-pipe under the intake manifold, stuck check valves, or clogged SA ports in the heads. Unfortunately, clogged ports are quite often the problem. This requires removal of the heads and drilling out the carbon. Some people over in the E65 forum have claimed success in opening up the ports using solvents and wire brushes, but I spent a week doing that with no success. So, it's head removal time for me. Fortunately, I have the means and the know-how to do the job myself.
I saw the YouTube having the video to show how to clear the clogged passage.

Last edited by Ricardo567; 01-25-2013 at 01:07 PM. Reason: No linkpage
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