I have an MDS that is giving me problems. It runs good at full throttle. Runs good at idle. Does not hesitate when going from idle to full throttle. While I'm flying I cut back once I'm up to altitude and it runs fine for maybe a minute then just shuts off with out warning. After a deadstick it starts right back up and runs fine. I have read many posts here looking for some kind of help. Some times I think maybe there isnt enough pressure pushing the fuel but then why will it idle? I have considered a fuel pump but dont know enough about them. I would think an engine like this would run fine without one. I have pressure tested the tank and fuel lines under water and found no leaks. The engine is fairly new. Any ideas?