'04 power lose when engine warms up.

I have a 2004 dakota quad cab 4x4 3.7 5m with 32k miles

I have a strange problem that I cant pin point the answer..

When the truck is cold it has tons of power! Accelerating between gears is strong with minimal gas pedal travel.

Once it reaches operating temp, The power dies down and it takes more gas petal travel between gears to accelerate. Even if I step on the gas hard, it doesn't accelerate hard at all. The truck feels like it cant get out of its own way...

Maybe once a week the power is normal no matter what the engine temp..

There are no engine codes and I did the usual tuneup..

ANY IDEAS?

I'd guess the coolant temperature sensor isn't working properly. I'd check the truck's timing at a high idle when it's cold and warm to see if it changes. The intake air temp sensor might also be part of it.

I can and will defiantly check those two sensors out..
Wouldn't they throw a code if they were bad though?

Not all the time the computer thinks the engine is always running cold. A good scanner will let you watch the signal. You can ask the parts stores who give free scans if they will do this for you. Just monitor the temperature the computer is getting. A stuck open thermostat will also throw the sensor off.
This you can feel when up to operating temperature by feeling the top hose.