Boris Johnson is opposed to more congestion charging, but not quite yet; however, he is also keen on "road pricing". I can see a couple of explanations for this.
One is that there's no "there" there - he's an unstable personality without intellectual substance and with a practised TV clown act, like George W. Bush, and therefore the various interest blocks around him push him this way and that according to the tides of City Hall internal politics. Standard cognitive biases lead him to believe that whatever policy is imposed on him, it's right and he believes in it. The petrol head faction demand their freedom to drive, or rather, sit in traffic jams, and they get it; the TfL civil servants and the Tory wets push back, and he gives into them as well. The Dunning-Kruger effect allows him to imagine that only he can integrate the two.
The other is that there is some kind of aesthetic/emotional/ideological distinction between the congestion charge - invented by Red Ken to harass free-born Englishmen with camera and database - and road pricing, which would make people pay what the service is worth, etc, etc. Road pricing suggests that roads might be a premium product; paying the price might attract status. Congestion charging is evidently something like a tax, and one that is levied on congestion; it's one of the great conservative rhetorical achievements that people in cars complain about the presence of other people in cars, aka congestion.
It's also true that London Tories and their surrounding infrastructure staked a lot of credibility on the inevitable failure of the congestion charge; the Evening Standard spent months in the run-up to its launch threatening and promising chaos, the Tory group in the London Assembly developed a heavily promoted charging spokesperson, and then...where is the earth-shattering kaboom? And, of course, a sizeable chunk of the budget is dependent on it. So it could just be rhetorical pretzel twisting to justify the policy to themselves.
Either way, this is all fairly typical of the irrational politics of the modern thinkers. Political unreason is how prejudices get expressed; so who gets the bill?
Bus passengers, that's who; not only are they disproportionately poor, eastern, central, and Labour (or rather, Ken Livingstone)-voting, but it's got to have some influence that they travel in rolling manifestations of "the group rights agenda". On the other hand, drivers are still being threatened with road pricing - is that, I wonder, code for bringing back the idea of GPS-tracking cars rather than just gating central London? Clearly, this isn't so much a strategy, as an uncontrolled drift that nevertheless shows a certain trend, demonstrating the underlying prejudices.
Unsurprisingly, we get quite a few "whoops, airport" moments: here's one. I have to say, appealing to "sheikhs" as the answer to financing anything deserves to be the standard marker of amateur hour. Knowing this lot, they'd manage to land Suleiman al-Fahim bidding without telling his dad.
Relatedly, compare this basically sensible post, quoting Mark Kleiman's suggestion that the bulk of the great reduction in crime from the early 90s might be explained by the elimination of lead in petrol, and Chris Dillow's post arguing that Boris Johnson ought to be held responsible for the same biological effects if he stops the expansion of the London low emissions zone. While it's abstract and generally Drum/Kleiman-esque, everyone nods and smiles; once Dillow spits in his eye, just watch the troll QRF come charging out, moaning and whining.