Asheligh,

There are several things that could be happening.

The Built in diagnostics are really good so you should have some codes (in the future get the codes from the Mechanic even if they reset them and the code doesn't return)

1. The transmission control module could have a problem and it might start you in 2nd or 3rd gear (use the manual mode to verify that you are in first gear when the problem is happening)

2. The Fuel Pressure sending unit could be faulty - if the pressure isn't what the ECU thinks it is then the power could be very low and then if the sensor works when it is warm then the power will return (this should set a code or at least have very high fuel trims and misfires) If the sensor is frozen and you have some water in your fuel then strange things might happen. How cold is it when you have the problem.

3. The Intake Variable Valve Timing Solenoid could be faulty - it is possible that the ECU limits power but it should set a code

4. Intake Variable Valve Lift Solenoid there are two - if you don't switch to the high lift state then you will have about 30 Horsepower instead of 230 Horsepower this will absolutely cause the type of problem that you are having (but once again you should have a code)

Good luck

Paul

PS with LAND ROVER you need to be exact. You wrote "I get the message saying Poor engine performance" but I think the actual message is "REDUCED ENGINE PERFORMANCE". I realize that they sound about the same but we need precise information to help you out.