Here is my newly acquired Jaguar S Type. It's a May 2000 4 litre V8 auto. I bought it without an MoT for very little money and have now done all the repairs to get it through its MoT. These were mainly replacing 17 rubber ball joint boots and freeing off the rear passenger door which could not be opened from inside the car or outside. The car had been standing in a field for many months and the damage to the rubber was caused by rodents. The previous owner owned the car from 6 months old until I bought it earlier this year (2015) but he didn't use it that much eventually leaving it parked on some land near his house. The mileage 47,000 miles but it had moss growing on it everywhere and some weeds had taken root in window channels.
Apart from the MoT failure it came with a number of other problems which I have gradually dealt with. The rear parking aid wasn't working and my scanner told me that one of the sensors had failed. It actually told me which one which fortunately was at one of the corners. These can be replaced by removing the rear light cluster. It's awkward but you can reach the sensor this way and it's a lot easier than taking off the bumpers.
The interior mirror had the common liquid crystal fault. I was able to find a replacement easily enough but getting the old mirror off proved to be a real problem and even though I was doing it in the correct way I cracked the screen and had to have it replaced.
I also had to replace the coolant expansion tank which is another common fault. It was cracked in two places and the engine was losing coolant. This is much more easily done if the brace is removed but the problem here is that the there a two bolts on each side that secure the brace into the top of the inner wing and these were rusted up solid. So rather than spend hours freeing these off and risking shearing them I found I could wriggle the tank out with it the brace in place. Removing the brace is a job for the future because it facilitates so many jobs around the engine, for example, accessing the coils and plugs.
I had intermittent misfires and had had to replace two coils in fairly quick succession. The Jaguar replacements are quite expensive but I found NGK ones available at a sensible price.
The rear subframe can be a problem on S Types because it can corrode which usually will result in scrapping the car. Mine has now been wire brushed and Waxoyled so I hope to have extended its life for a year or two.
Remaining preventative maintenance will be to replace the upper chain tensioners with the latest aluminium ones, replace the water pump with the type where the impeller doesn't fall off and change the oil and filter in the transmission.