1.6 Zetec S Engine Problems

Hi there,

I have a 2000 Focus LX that has the 1.6 Zetec S (silver top) engine fitted that has just covered 100K. There are a few issues that have recently cropped up.

1) There is a missfire that occures randomly at speeds over 30 M.P.H. more often between 60 and 70 M.P.H. where it stutters/stalls for about 1 second, it's had a new coil pack, plugs and leads but still no better.

2) The temperature gauge when going over 50 M.P.H. rises all the way into the red, the cooling fans come on but the needle stays there, i have checked the water imediatly when this happened the first time and it was normal not hot like the gauge would suggest. When the speed drops back below 50 the needle then drops to the normal position in the middle of the dial, this has only started after I had fitted a new engine temp sensor (ETS). The cooling fans are coming on more often as well, but i'm not sure if thats a fault too or a concequence of the information sent to them from the sensor.

3) When changing the ETS i noticed condensation in the area inside the cover(also on the spark plug leads/boots).

there is also a treacle like substance at the bottom and around the plugs that i can only think might be engine coolant that has become condenced as it is a similar colour.

Any help with these would be greatly appeciated.