2005 24V won't start after running perfectly for a couple of hours

[jjrtar0325]

Hi, our 24V has been working perfectly but have gotten stuck out on the lake twice in the last 2 weeks. Boat is running fine and if you stop for 30 minutes to an hour to swim, it will not start. Turns over and you can hear the fuel pump hum but will not catch or start. My mechanic came over and said I had a code 33 so he replaced an ICM sensor and again it was working fine until yesterday. Any ideas? Could it be vapor lock? We have the 6.0L GM marine power engine. Thanks for any help.

[jjrtar0325]

Hi, our 24V has been working perfectly but have gotten stuck out on the lake twice in the last 2 weeks. Boat is running fine and if you stop for 30 minutes to an hour to swim, it will not start. Turns over and you can hear the fuel pump hum but will not catch or start. My mechanic came over and said I had a code 33 so he replaced an ICM sensor and again it was working fine until yesterday. Any ideas? Could it be vapor lock? We have the 6.0L GM marine power engine. Thanks for any help.

Diagnostic Software says it might be a manifold voltage sensor but can't get it to run long enough to get all codes downloaded. Seems like lots of sensors with the EFI. Any ideas?