This may have been some form of error on my part during the reading of the question. For whatever reason, my mind took the phrase 'coup' as something much more public or, I supposed militarized than what happened to the USSR. Perhaps that is an incorrect way of looking at it. Call it a recent subconscious bias over what happened to Venezuela putting that interpretation at the forefront of my mind. China would undoubtedly repel Maduro-esque coup, and if the US were somehow successful in capturing Xi, it would have hell to pay in the sanctions it would recieve within the hour alone.

I also suppose that you could make an argument that because China has not gone through a period where the party line gave way to revisionism, the remaining party members would have more political capital to organize loyal factions of the PLA and the massive CPC membership to stage a counter-coup. This almost did happen in the USSR with the 1991 coup attempt at removing Gorbachev from office from more principled party members. I imagine that, were a sudden coup to just simply happen and some stooges were put in power in China, a similar chain of events would occur with a much more effective resistance measure due to the more principled party line at the moment. Take that interpretation with a grain of salt, as I am still brushing up on my Soviet history.

However, were the phrase 'coup' to mean something like what happened in the USSR—Yeltsin illegally dissolving the USSR after many decades of revisionism already rotting the party internally, and economic hardships on the people—this could cause a different series of events to happen in China. Even in the USSR though, there was an attempt at overthrowing the revisionist government. In China it would be a matter of questioning whether the revisionists would win in the military conflict or not.

Again, don't take my word on the conjecture of the latter parts too heavily comrade, I may be mistaken, as I am still learning myself. :)