engine stall at idle

goalie59

Was wondering if anyone might have any suggestions on a strange stalling situation that happened the other evening. We were coming into our marina after a 45 minute cruise . idled down at the no wake zone and made our way to the slip when the starboard engine beeped once and then stalled. It imediatly restarted and then a few minutes later the same thing happened to the port engine, one beep and then stall. After docking i tried it several times and all is working well. Iac valves were replaced two years ago,along with plugs ,rotor, caps and wires. New fuel filters in the fall winterize process. The boat is a 2005 Rinker 320 with twin 350 bravo three. One thing to note is that it was very hot outside temp but being that they imediatley restarted I don't think it was a vapour lock. Any help would be appreciated. Thanks  

pistole

throttle position sensor

goalie59

Would a fault set a code or maybe it was just the heat. Have you experienced this before. Thanks for the info

212rowboat

likely heat... likely guardian kicking in to reduce fuel flow and killing idling engine... 

coming off plane to wake speeds reduces the flow of water through the blocks, manifolds and risers right when they need it most... it's the equiv of shutting down a car engine immediately after running it hard, waiting a few minutes and firing it back up- you'll find it's hotter then than it was when it was shut down.  this is why slowing down incrementally when heading into a no wake zone is a good plan- it allows the engine to get the water it needs instead of starving it.  

goalie59

Thanks for the suggestions. I replaced both iac valves and the passage filter two seasons ago, I pulled the filter out and it did not look that bad. Not to sure what you are referring to Al. Is it possible that the throttle position sensors are faulty, they are original at almost 13 years old. Also when the engines stalled there was only one audible beep, is this normal when the engine stalls in gear ? 

goalie59

Thanks Al. Plugs,cap,rotor ,wires,iac valves and filters ,pcv  valves two year and 90 hours ago. I will get the engines scanned but if there were no fault beeps would there be codes ?

goalie59

Update . No codes or problems detected. Replaced both iac valves and problem seems to be fixed. One thing I did notice after replacing valves  is that at idle the port engine idles faster as the sync gauge is moved all the way to starboard.