Loss of power

Starts okay and drives okay, but loss of power is weird. Straight road is fine but takes a while, slight incline and doing 61mph and from 6th to 5th and 4th and 38mph. At standstill revs fine and when driving the same but apply power and nothing. Dip the clutch at any speed and rev it with not a problem. Checked all cables/wires etc, also plug sockets to most of the sensors, everything brand new. Before this started it was running normal, I changed oil and filter and air filter etc, checked brakes front and rear, changed front wheels with the rear wheels. Don't have a spare fuel pressure sensor to try but I'm a bit miffed as I bought it new and I do oil filter change etc, etc, every 3,000 miles. One thing I did notice was after I removed the service light (not immediately) the engine light came on with the service light then warning the dpf might block, so took it for a steady 50 mile before and it didn't come back on. But no cruise control or limiter even though they shows on the dash. Help!