its on the front of the block on top of a black plastic housing with two water hoses going into it. check for any leaks round the crankcase breather bung (the flat, round thing on top of the rocker cover) it might well help to take off all the hoses connecting the ISV to the inlet and clean them out and possibly the throttle body with carb cleaner. then once everything is how it should be get the car running up to temperature (till the fan kicks in) then remove the blue plug from the temp sender, rev the car over 3k letting it drop to idle then you can adjust the idle speed with the little flat head screw in the throttle body. switch off, re connect the blue plug, wait a minute and start it up again. it 'should' be fine!