My friend’s Eagle had an issue recently where it refused to idle below 1600rpm in flight. He had to pull its mixture to idle cutoff on short final to land recently. This occurred on the return leg of a short cross country flight with less than an hour between flights. A ground run after landing had it idling at 1200rpm. We pulled its cowling a couple days later and everything appeared fine with all the linkages and linkage travel on its RSA injection, no throttle binding or anything else; the throttle butterfly valve looked fine as well. Another ground run had it idling at 1100-1200rpm. Didn’t need much adjusting on the idle stop to bring it down to 700rpm. We buttoned the cowling back up but weather prevented a test flight. It’s only a couple hours since condition inspection, and we did all the usual maintenance items like cleaning fuel and air filters, etc. Lycoming troubleshooting guide has a separate RSA injection section but nothing really applies. Engine runs fine otherwise. Any ideas before we try flying it again? P.S. I’m an independent A&P/IA but haven’t run across something like this before.
Larry
Larry