I decided to have another crack at my troublesome car over the weekend. Bought a spark tester and result was that it has a strong spark on all cylinders when tester set with gap at about 8 mm. However the spark was orange/yellow. I would have expected to see a blue spark but maybe that's not the case with a coilpack?
I'm at the point where I think I need to take the car to someone who has good diagnostic equipment. If I have a fuel pressure problem for example, is this something a diagnostic device that reads real time data would pick up? it's hassle to get the car to a garage so I just want to ensure the time and money involved would be worth it.