Yesterday my 40EFI started to miss and lose power. It seems like it is running on 2 cylinders. Where should I start. It is a 2007 but has less than 100 hours.
Make (of engine): Merc
Model (of engine): 40ELPTEFI
Ser 1B270136. I have removed the engine cover.
Hi, My name is XXXXXX. XXXXX you for letting me try and assist you with your problem.You need to start with basic tests.Check compression. Each cylinder needs to be within 10% of each otherReplace spark plugs and check for spark on all cylinders.If you have good compression and spark and it still doesn't run right your problem is going to be fuel related.It could be contamination in the vapor separator tank.There's an electric fuel pump in the tank that has a filter on the bottom of it.You can open the vst, remove the pump and clean that filter.Something else to try is to squeeze the primer when it starts to act up.If it helps you need to rebuild the low pressure fuel pump.If it makes it worse you need to rebuild the low pressure fuel pump.If it makes no difference it's going to be the high pressure pump or a faulty injector.
I am just a novice, I could not see the spark plugs, do I have to remove something to access them?
You have to have the cowling off.They're on the back of the engine.