Can anyone shed some light on this problem? My ‘96 855 keeps turning on the check engine light with a code P0410 – secondary air injection system malfunction. The problem has been there for about a year and a half. I bought an OBDII code reader/resetter so I’ve been reading it and resetting it forever. I’ve been working though this with my mechanic, who has been good about trying to avoid unnecessary repairs, but this is just not getting resolved. At first he just cleaned the system and reset the CEL. That only lasted a month or two, so he did it again. The light was still coming on about 4 days after each time I reset it. Finally he broke down and replaced the pump. That lasted a few months, then the CEL came on again. Then he replaced the valve. No dice! The CEL still comes on about 4 days after a reset, even though the pump and the valve are both new. Is there anything else that could be wrong? Could it be a faulty pump? My mechanic says it tests out OK – spins up to speed with power applied, etc. I’d be happy to hear about any similar experiences…