5.7 Gxi B stalls after abrupt throttle change from cruise to idle

[dness]

Replaced the main fuel pump and pressure regulator at the start of last season. Near the end of the season after a 20 minute run at 3500 rpm I pulled the throttle back quickly to idle and the engine stalled when the boat settled down off of plane. Would not re-start at normal idle throttle position and I had to use the neutral lock-out to give it a higher throttle position and it finally sputtered and then fired up ran fine. Same problem occurred again recently. It only seems to happen when I pull it back quickly after running on plane for a while. Last nigh,t in fairly rough seas, it quit after coming off of a bigger wave and it did the same thing and required the same starting procedure. Normal power and acceleration at all other times. Any ideas?

 

[alldodge]

I would remove and clean the IAC to start with. It might just be gummed up. Clean with mild soap solution and no chemicals. Look at the valve and its seat

Do the same cleaning with the IAC muffler (the small piece of foam material in the throat of TB), and flame arrestor

 

[dness]

Dodge, great advice! Took me a while to get the part and install it but it seems to have solved the problem. Ran great today! The old valve was pretty dirty with a lot of very black oily residue on the stem and seat. This boat spends a lot of time running at idle speed while trolling for salmon on Lake Michigan so that may be a factor in the build up of crud around the valve. Anyway, THANKS!! Very inexpensive solution and restores my confidence in the boat.