In Australia the spending on roads etc jumps around madly year to year. The revenue comes at the state level from vehicle registration fees of around $1,000 (depending) and fuel excise (ie some cost per litre).
This tells us that the road spending is about $69 billion and the revenue $45 billion. Motorists already pay most of the costs of roads. The excise is $0.423/lt on ordinary petrol. Let's say we double it so that the total revenue exceeds the road costs - the fuel price would rise $0.423/lt. Now, that sounds like a lot, but in the last year before the OPEC price war and virus, fuel prices have varied between $1.20 and $1.75/lt, and it didn't have much effect at all on consumption. That is, the normal price variation over the course of a year was greater than what a doubling of the fuel excise would achieve - and people still drove a lot.
Now, I don't object to this as such. People should pay for what they use. But if you want to discourage people from driving larger vehicles, or from driving a lot, a simple consumption tax with no accompanying measures doesn't work.
Taxes on tobacco worked to reduce consumption because you don't have to smoke. But you do have to have transport, particularly if we've designed cities so that our workplaces are far from our homes - good old residential suburbia full of NIMBYs. If I've bought a house 30km from work (because that's the only place I can afford to buy) and there's no local public transport to that workplace, well then I'm going to drive whether petrol is $1 a litre or $3. Because spending that money on transport enables me to earn more money than the cost of that transport.
Obviously, if the price of transport exceeded my earnings, I would then stop. If it costs $200 to get to work and I earn $150 at work I'll stay home and not burn fuel. And there's probably some point of cost before my daily earnings of $150 where I'll stop and not bother. However, the basic issue is:
I have no alternative.So if we were to increase the petrol tax (or vehicle registration, or bring in a congestion charge, whatever, same shit, different shovel) then we'd have to use the revenue to offer options. Give me cheaper housing closer to work, and/or improve public transport. It's like with my kids: if I just tell them to eat their dinner, they don't. If I tell them, "dinner, or bed? your choice!" then they scarf it down.
Don't merely tax the thing you want to
discourage, offer alternatives you want to
encourage. Like the people I train in the gym: I don't just tell them, "don't do that", I add, "do this."