Engine is giving me a hard time

Hi

My 350Q engine is given me a hard time. The engine always starts right way, idles good and WOT rpm is also good (about 300 rpm high but I think I have the wrong prop). I usually drive at around 1500 rpm in the channels around here or cruises arounf 3000 rpm.

The problem is that the engine suddenly dies without any warning. This happends at all different speeds. Alos sometimes it loses rpm and then rpm goes right back up again but usually it just dies.

I can normally start the engine again and then drive for a while agian until it happends. This can happened to me 30 times one day and then just once the day after. But it usually never happends when the engine is cold. Sometimes when I try to restart it nothing happends (the starter doesn't turn) but when I try again after two minutes it starts turning and the engine starts. In order to start it I have to turn and hold the key for a while before the starter starts turning.

I have removed the flame arrestor after the engine died and pumped gas and gas is coming directly. I have also tried running without gas cup and I have pump out fuel but there were no debris in the fuel. Also have changed all filters.

Engine runs nicely when it's running, no smoke and sounds nice. But you can clearly hear that it is soaking air (but maybe that is normal?).

Yesterday I went for a long ride and the engine died 20 times in a short row. I then had to drive home at 1100 rpm, took us about 2 hours but the engine didnīt die when I stayed at 1100.

I am going out to the boat tomorrow to try and check all wiring. I think that it smell a little burnt from under the dash after about 20 starting attempts during 10 minutes yesterday. The engine started 10 times and then diead. Then I waited about 3 minutes and the engine started and we went home on idle.

I am inexperienced so any ideas of what I should look at and how to do it would be appreciated. We are having the Lancer/Commander 23 club meeting her next weekend and about 40 boats are expected. I would be nice to go and to take some photos for the forum but I am not trusting the boat right now.

Hope you all have a nice summer.

Regards

Rickard