Fuel delivery problem?

The symptoms you're describing could be caused by a few different issues, but given the fact that you mentioned the fuel pump whining loudly, it's possible that the fuel pump is failing or not providing enough fuel pressure to the engine.
Here are a few things you can check to troubleshoot the problem:

1. Check the fuel filter: A clogged fuel filter can restrict the flow of fuel to the engine and cause similar symptoms. Check the fuel filter and replace it if it's dirty or clogged.
2. Check the fuel lines: Make sure that the fuel lines are not kinked or damaged and that there are no leaks. A damaged fuel line can cause a loss of fuel pressure and lead to a bogged down engine.
3. Check the fuel pump: If the fuel pump is whining loudly, it may be failing. Check the fuel pressure with a gauge to see if it's within the manufacturer's specifications. If it's not, then the fuel pump may need to be replaced.
4. Check the spark plugs: Make sure the spark plugs are in good condition and properly gapped. Fouled or worn spark plugs can cause a loss of power and bogging down of the engine.

If you're not comfortable performing these checks yourself, it's best to take the snowmobile to a qualified mechanic who can diagnose and fix the issue. text me on Whatsapp +233557248347

This can be related to a couple of issues, the most common of which are:
1. Fuel delivery problem (e.g. the fuel pump produces too low fuel pressure or the fuel pressure regulator can be shot or the injector(s) may be clogged). When you step on it, it leans out and has no power.
2. Air delivery problem or air metering problem:
- a clog in the air intake (I've once had a mechanic leave a rag in the air filter box and the car wouldn't want to accelerate)
- airflow sensor
- map sensor
- throttle position sensor
3. plus, the searching can be a symptom of a shot idle air control motor (stepper motor), but this won't fix the loss of power so I'd suggest leaving it for later, after the loss of power problem's fixed.

I would suspect the fuel pump fuse, relay, or the pump itself has failed. Turn on the ignition without starting the engine and listen for the pump to run for a few seconds before shutting down.

Was the fuel tank cleaned out when the pump was replaced? You could be sucking up garbage from the bottom of the tank to the fuel pump strainer causing the loss of power, Then your shut it off and the garbage comes of the strainer and you have power again

could be a fault with the fuel pump. it may be wearing out. check the fuel pressure at delivery. a blocked filter can also do this as its being surged for more fuel not the normal filter this one is on the pump it has larger holes and if you have sludge in the tank this can stop the fuel delivery. . for vacuum leaks spray some carb cleaner around the air lines any change in the engine usually indicates an air leak. also the fuel pressure valve these can all lower or stop fuel pressure.

Yes, this is indicative of fuel pump failure. It will need to be replaced.

It sounds like you might have a clogged catalatic converter on the exhaust system.

NHTSA ID: 05V266000 Issued: 06/20/05 No. of vehicles: 00078675
Fuel system, gasoline:Delivery:Hoses, lines/piping, and fittings
on certain pickup trucks and chassis cab Vehicles equipped with 5.4L
or 6.8L gasoline Engines, the fuel jumper line may have an incorrect
end form.
The fuel line may separate at the connection to the main fuel
bundle. If the fuel line separates, an operator may notice a
gasoline odor and/or fuel on the ground, loss of power, and the
Engine will eventually stall. Fuel leakage in the presence of an
ignition source could result in a Fire.
Dealers will install an external retention clip at the fuel jumper
line to the main fuel bundle connection. The recall began on June
20, 2005. Owners should contact Ford at 1-800-392-3673.

sounds like it could be the fuel pump. I had a simular problem with an astro van. does it restart with full power after you shut it off and wait 15-20 minnutes? if if does i would have the fuel pump pressures checked.

I sounds like a fuel delivery problem, I would first check the filter -above the rear axle- if it's clear, test the fuel pump delivery. ps; the original filter elements are hard to get, we usually fit a good in line unit instead, leaving the original filter housing in situ. Also, unless they are fairly new now is the time to replace the fuel hoses back there.