My car is burning a lot of oil - do oil additives actually work to fix this issue?

My 2005 Ford (petrol engine) has started burning quite a lot of oil and I can't find an external oil leak. The car has done 100,000 miles and has been serviced regularly. I'm not keen on embarking on expensive...

My car misfires every few weeks - why does one spark plug always get oil on it?

Every few weeks I have to take the same spark plug out to clean oil off of it because it starts misfiring. Could you please tell me what the problem may be?

What's wrong with my Chrysler Voyager?

I own a Chrysler Voyager (2000 model). When travelling over 3000rpm, it leaks oil over the top of the dip stick. It has also developed a misfire. Any idea what could be causing this?

Jaguar X-Type (2001 - 2009)

Compact Jaguar, launched as V6 only with four wheel drive. Held price well at first.