When i put my foot down i have an increase in engine revs but no increase in road speed i also have an ocasional loss of speed. it is a 2.5 dse auto model.

check your throttle position sensor

check the rpm and road speed when this happens . The cruise control will increase to keep RPM constant but as the road speed drops the auto may be shifting down and as the rpm increase it shifts back before the rpm adjusts. You can override a cruise control in this situation by simply pressing down on the accelerator to maintain the power setting and road speed and when the situation is passed and you take your foot of the accelerator the cruise control will return the system to the set position without you needing to do anything

Not necessarily, There are numerous factors that one must look into. If it where clutch you would feel it on pull away. Clutch slipping and smelly. However loss of speed occurs over time, if you don't service your vehicle thoroughly and on date, then all sorts of problems will arise. Wheel alignment is also what i would look into. Old oil that has over time lost its viscosity may lead to engine losing its power. Tyre pressure. Fuel filters. Oil filters. Injectors. just to name a few.

The transaxle is gone, by what your discribing,slipping
real bad

You also said the coolant was low ??

I would say it is time to park it and make some choices.

Do you want to invest money into a 15 year old car?

I wouldn't

Sounds like something is overheating then and possibly a sensor. Not familiar with Rovers but might be a problem with the CAS and/or CPS which tells the ECU the motor is running and when to fire. Also maybe the IAC is bad and when you go from throttle to idle it can't control it and allows it to die.

To confirm the clutch is slipping , drive at about 35mph in 5th gear and then put your foot to the floor (making sure the road in front is clear!) IF the engine note increases along with the revs and the speed stays the same then it is the clutch that needs replacing.

Simple answer, no, it will not most likely cause any increased wear to your engine or transmission. Yes, it is normal for the engine to rev while climbing a hill while in cruise control.

The cruise is designed to be used on flat (or semi-flat) stretches of highway at 55mph or higher so you don't have to hold the fuel pedal the whole time and your foot doesn't get tired. The cruise control system will try it's best to keep your vehicle rolling at the set speed, increasing/decreasing the throttle to compensate for changes in engine load.

If you are driving with cruise on, try lightly putting your foot on the pedal and you might notice that the system will actually move the pedal itself. If you are in cruise, and you come up to a large hill, try putting your foot on the pedal and getting it up the hill on your own w/o cruise then resetting cruise once you are off the hill.

Also, cruise is not supposed to be used in moderate/ thick traffic or on country roads with a lot of rolling hills. The cruise control system is a "dumb" system meaning (not that it's pointless) but it will only change the pedal as the speed changes and it has no idea what's coming up next, even while you are already on the hill.

So, it is normal operation of the cruise control to try to compensate for a hill by constantly revving up the engine and letting it fall back down to try to keep moving at the exact same speed you set it for. If this is a bother, you can always use your foot to hold the pedal while climbing the hill normally.

Don't worry, it won't cause any increased wear and tear on your vehicle. I hope this helps. Good luck and don't forget to rate! Thank you!