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jcurtis
03-20-2008, 01:22 PM
I have a 1999 230 Maristar VRS with the 330 HP motor in it. I had it at tahoe this past summer and the engine would not idle, the RPM would rise and fall. Once I got it above 1500 rpm it would run normal until I come off the throttle, then sometimes the engine would die. It seems like the computer is confused and is searching for the right combination. Back at sea level everything runs great. I had a mobile mechanic hook it up to his computer and he couldnt find anything other than maybe the fuel pump was bad. Has anyone heard or know what the problem may be?

flipper
03-20-2008, 02:40 PM
I've had that problem with carbs, but not EFI...just givin a bump

André
03-20-2008, 06:45 PM
I have a 1999 230 Maristar VRS with the 330 HP motor in it. I had it at tahoe this past summer and the engine would not idle, the RPM would rise and fall. Once I got it above 1500 rpm it would run normal until I come off the throttle, then sometimes the engine would die. It seems like the computer is confused and is searching for the right combination. Back at sea level everything runs great. I had a mobile mechanic hook it up to his computer and he couldnt find anything other than maybe the fuel pump was bad. Has anyone heard or know what the problem may be?
Bad MAP sensor?
Altit-de sho-ldn't affect m-ch on an EFI engine...

cbryan70
03-20-2008, 06:53 PM
Arnt gas mixtures different at different altitudes? At least this is what one of my math professors told me. Did you bring the boat with a full tank? Maybe thats it?