I do not understand how the weight of a spare wheel is going to add 9 g CO2. To What? If the author means that CO2 emissions will increase by 9 g CO2/km, then I understand, but totally disagree with the figure. It is a widely held belief that extra weight in a car will increase fuel consumption. It may, but it is not inevitable. It depends on the driving style of the driver. Even if it does have a negative effect, an increase of 9 g/km is doubtful. Take a car which averages 45 mpg. If it is petrol powered, it will emit roughly 147 g CO2/km. If an extra 20 kg increases that by 9 to 156 g/km, that is equivalent to a fuel economy figure of 43mpg, a reduction of just under 5%. That extra 20 kg, somewhat less than 2% of a typical car will not affect air resistance, rolling resistance or engine efficiency. It is thus improbable that such a small increase in total vehicle weight should have such a large effect on fuel economy under normal driving conditions. Where extra weight does have a negative weight is when you do a lot of braking - and that occurs during the extra urban part of the EU economy tests. So leaving out a spare might reduce emissions sufficiently to drop an emissions band, but it will not be reflected in the driver's experience. Therefore, R.L. Nunn may safely put his spare back in the car without worrying about its effect of fuel use. Even a space saver spare is better than a repair kit since it will not ruin the punctured tyre, and be more reliable.

If this is on the driver side,then I would suspect this is the grommet where the bonnet release cable runs through onto the engine bay.It needs to be sealed against the bulkhead.

Likewise, I have driven hundreds of thousands of miles with diesels, ever since they had EGRs in fact and I have never had a problem.

I think that learning is always a great idea. I was born in the age of millennials, but it is not a problem for me to pass the driving or any other test. I think it is related to human psychology. I have recently wrote a paper on this subject and found a lot of useful information on this resource https://writingbros.com/essay-examples/psychology/ for students. Maybe if someone create such sites about driving, young people will be glad to drive cars :)

I agree that the driver must be prepared. Even when I wrote a paper with edubirdie.com/statistics-help about driver test passing results, I had about the same numbers. All the same, the test needs to be done where you live so you will be prepared for the real situation on the roads.