Being an individual, it is almost impossible to manipulate bitcoin price unless you have few millions to trade in crypto currency market. However, if you have a group of traders with you with good numbers of investment, you may try to put some fake trading requests with good volume and you wish may be fulfilled. But the chance is rare.
Check the market cap of bitcoin. So it is not possible for an individual to fake bitcoin price. A million dollar may come handy there. Just a suggestion!
Bitcoin is only can manipulate by blocks. Apart from that no any organization or individual person cannot able to control over btc. If it may control by government when the bitcoin become a centralized and when the government take over it.
There is far relation between technical aspect and economic aspect of a coin when it comes to price manipulation. I believe it is the economic / financial aspect that is active in this field. These people are traders, different kind of. These people may use technical issues, news, worldwide economic etc. to affect and influence the price of Bitcoin.