Car Temperature rising at higher speeds

[rasputin]

When i drive at around 40-50MPH it will stay around 90 deg but when I drive up to 120MPH the temperature reaches well over 90 deg on the dial, close to 100 deg
I had the coolant, thermostat and temperature sensor on the engine block recently.
Its a 1999 Xsara 1.4 with a TU3JP engine.
Any help much appreciated!

[Northern_Mike]

Well, it'll only actually officially do 107mph and you're working the engine really hard at that speed, so of course the temperature is going to go up.

Your radiator is probably getting silted up, could be due to the headgasket beginning to fail. Not uncommon in those engines.

[SaabC5]

120mph with a 15 year old 1.4 petrol engine! Is this downhill with a sail on the roof?
On a serious note any small "family" car is gonna be running hot at speeds in excess of 100mph, they are not designed to run for long periods at excessive speeds. You may find flushing the cooling system with a propriatory cooling system flush may get rid of some of the silting and allow the engine to run a little cooler though.

[Peter.N.]

I would agree with most of the above but if you do have a fault it will most likely be due to a clogged radiator.

Peter

[rasputin]

It was just to test and see would the reach higher than 90 deg, only for a min or two. I don't drive at this speed at all as I know how this can effect this car. I know before the coolant change this was not an issue if I did reach 120MPH. I did flush before the change too.
Thanks for your replies!

[Old-Guy]

You could try bleeding the cooling system again.