Hi,

The clatter when it was cold outside last week and before then actually retarded the power, i.e. it did not accelerate as quick as when warm, I take it from the above two posts that the lifters are hydraulic, if so then the quality of oil would make a big difference in the cold so next question is....do I put Mobil 1 in or similar for cold weather running?

cheers

You have a very good point - the optimum temprature for economy is (apparently) 192 degrees farenheiet (88.8 degrees centigrade in tests on Ford (diesel!) trucks)

The Mondeo takes "ages" to warm up and when it does the temprature struggles to get much above 60 degrees

I don't know the optimum temprature for performance for a diesel but i know its lower than 88.8 degrees but probably higher than 60 degrees

The glow plugs only really heat the combustion chamber enough for starting and the engine needs heat in the bores, piston head to run right / run efficiently because it is a compression - ignition engine and requires heat

On a cold day when the engine temp drops (normally after running the cabin heater) the MPG can drop too

Now that i have a digital temprature gauge/ controller and electric waterpump, im going to experiment with adjusting the temp to find the optimum temp for performance, but im pretty sure the engine does not run well untill 50+ degrees/ runs badly under 50 degrees (gauge starts at 40)

The above is for diesel engines, of course, petrol is a different kettle of fish

The Mobil 1 / castrol magnatec/ quality oil should protect the engine better from cold, the engine should be quieter (esp from cold) and last longer before needing an oil change, may even have slightly better performance/ economy

The question is - is cheaper oil changed more frequently better than expensive oil changed less often?

I was aiming more at the viscosity of the oil because there obviously seems to be a drag in cold weather on the top end,not getting any symptoms at all now the temperatures have risen,?